Home

ACCESS Rack Product Manual

1. THIS SOFTWARE IS PROVIDED AS IS AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES INCLUDING WITHOUT LIMITATION THE IM PLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTIC ULAR PURPOSE All Equipment manufactured by Comrex Corporation is warranted by Comrex against defects in material and workmanship for one year from the date of original purchase as verified by the return of the warranty regis tration card During the warranty period we will repair or at our option replace at no charge a product that proves to be defective provided you obtain a return authorization from Comrex and return the product ship ping prepaid to Comrex Corporation 19 Pine Rd Devens MA 01434 USA For return authorization contact Comrex at 800 237 1776 or 978 784 1776 or email techies comrex com ACCESS Product Manual This warranty does not apply if the product has been damaged by accident or misuse or as a result of service or modification performed by anyone other than Comrex Corporation The next two paragraphs apply to all software contained in this product WITH THE EXCEPTION OF THE WARRANTIES SET FORTH ABOVE THE PRODUCT MEANS COLLECTIVELY THE HARDWARE AND SOFTWARE COMPONENTS IS PROVIDED STRICTLY AS IS COMREX CORPORATION AND ITS SUPPLIERS MAKE NO WARRANTY EITHER EXPRESS OR IMPLIED INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTIES OF MER CHANTABILITY FITNESS FOR A PARTICULAR PURPOSE OR WARRANTY AGAINST LATENT DEFECT
2. For example to initiate a connection to the Comrex test line at port num ber 5004 enter the following into the IP address field 70 22 155 131 5004 Note The call will fail unless the ACCESS on the far end is set to receive data on that port ACCESS Product Manual BACKING UP A CONNECTION ACCESS features an ability to have an automatic backup to IP remote con nections The backup may be either another IP connection or a POTS phone number Automatic backup works as follows If an IP connection fails ACCESS will sense this and wait the amount of time designated in the Local Timeout parameter in the profile assigned to the primary connection If the connection is restored in that amount of time no backup will occur If the timeout period passes without restoration of the primary connec tion ACCESS will automatically establish a connection POTS or IP to the designated backup connection It will maintain that connection until manually disconnected Backup connections are enabled and selected on the Change Remote Set tings option on the Connection Tab shown as 1 Figure 31 GD CHID ACCESS GID Ga DD be FW 2 8 p13 test4 FLASH GUI 2 80 Connections Statistics Audio Metering Profiles System Settings REMOTE ACCESS UNITS Name Address Current State Receive Status Profile Last Stat CHANGE REMOTE SETTINGS CONNECT Loopback 127 0 0 1 not conni weus NAME Keren POTS Test Line Comrex Lab Voice 70 2
3. TRAVERSAL SERVER SETTINGS s sssssessssesesssereseerenensersnserenenrenens 72 FIGURE 40 ENTERING NEW vn 73 FIGURE 41 SwWiTCHOARD TS MAIN ACCOUNT ACREEN 74 FIGURE 42 SWITCHBOARD TS REMOTE rer 74 FIGURE 43 SWITCHBOARD TS ENTRIES ON THE WEB BASED INTERFACE 0 00 000005 75 FIGURE 44 SWITCHBOARD USERS rer 76 FIGURE 45 SWITCHBOARD CONTACT rer 76 FIGURE 46 CHANGING ACTIVE CONTACT Lier Z7 FIGURE 47 SHARE A Dreck 78 FIGURE 48 MULTI STREAMING ARRANGEMENT 0eccecccecsccesscecceseecetsuessensseuseuaess 82 FIGURE 49 TRANSMIT ON OFF IN THE PROFILES Tan 83 FIGURE 50 MULTICAST SELECTION IN THE PROFILES Tag 85 FIGURE 51 GATEWAY CONNECTION cecsecsecseecseseeeseseeeesceseseeeesessesuetseseseens 87 F Gure 52 TCP IP TAB FOR GATEWAY Arm 88 FIGURE 53 N ACIP SIP Arm 91 COMREX CORPORATION About Comrex Comrex has been building reliable high quality broadcast equipment since 1961 Our products are used daily in every part of the world by networks stations and program producers Every product we manufacture has been carefully designed to function flawlessly under the harshest conditions over many years of use Each unit we ship has been individually and thoroughly tested Comrex stands behind its products We promise that if you call us for technical assistance you will talk directly with someone who knows about the equipment and will do everything possible to help you You can contact Co
4. 27 FIGURE 16 AVAILABLE FACTORY Dor 28 FIGURE 17 PROFILE SETTINGS FOR A NEW PROFILE cccccccceccscecsecuceeseccsseesusens 30 FIGURE 18 SYSTEM SETTINGS Jang 31 FIGURE 19 USER INTERFACE Tag 32 FIGURE 20 WEB BASED INTERFACE LOGIN SCREEN ssssssssesisssssesrreserieeseerses 34 FIGURE 21 WEB BASED INTERFACE SCREEN cccccccsccccccccccecceccssecsesuceesucsssuseusens 35 FIGURE 22 STATISTICS TE 37 FIGURE 23 AUDIO METERING Zap 38 FIGURE 24 PROFILES TAB viccccccccccccccccsccuccsecucssecssccucssssusssecseseucssssuesueseesens 39 FIGURE 25 CREATING A NEW PROFILE icccccscecsccceesecenecescueseeseeseuseessuetaeseeeens 40 FIGURE 26A SYSTEM SETTINGS ap 48 FIGURE 26b SYSTEM SETTINGS ap 49 FIGURE 27 CONNECTION TAB wicccccccsccseccuecccesscusccuccsuesscessesesuesueeseesseuseeness 54 FIGURE 28 STORE NEW REMOTE IN THE CONNECTIONS Zap 55 FIGURE 29 CONNECTIONS PASSWORD IN THE SETTINGS TaAp 57 FIGURE 30 CHANGING THE UDP PORT FOR INCOMING CONNECTIONS 0 00 00 58 FIGURE 31 BackuP FAtt FORWARD FUNCTIONS IN THE CONNECTIONS TAB 59 FIGURE 32 24 7 OPERATION IN THE CONNECTIONS Taup 62 FIGURE 33 POTS Copec vs POTS STEREO MODE IN THE PROFILES TAB 64 FIGURE 34 CONNECTIONS TAB DURING AN ACTIVE POTS Cant 65 FIGURE 35 THE EFFECT OF NA 68 FIGURE 36 SWITCHBOARD TS BUDDY rer 69 Figure 37 INCOMING PACKETS HITTING NAT Roum 70 FIGURE 38 PUNCHING A HOLE IN A NAT Rom 71 FIGURE 39
5. About ACCESS BGAN BGAN AAC ELD POTS AAC Mono AAC Stereo 1 HE AAC Mono HE AAC Stereo HE AAC V2 Stereo AAC LD Mono 1 AAC LD Stereo i AAC ELD Mono AAC ELD Stereo Linear PCM FLAC Remove Set Default i U tory Profile Fl Menu Arrows Enter Navigation Figure 15 Configure Tab Pull Down Menu Because ACCESS has many options to optimize individual connections it includes the concept of Profiles which allow you to define the behavior of a connection in both directions Profiles are separate from the concept of Remotes which define the address to which to connect A pre defined Profile can be assigned to multiple Remotes and multiple remotes may be defined to the same address which can have different profiles 27 COMREX CORPORATION 28 ACCESS comes with a series of profiles that are optimized for the majority of IP and POTS connections Many users may never have the need to define their own profiles But many advanced options are available to help with troublesome remotes or remotes with special requirements In this way you can build a profile having these advanced options and assign them to one or all remotes you ve defined When using ACCESS the point where the connection originates controls all available connection parameters in both directions Keep in mind that these profiles are useful only for connections initiated from the local ACCESS Incoming c
6. Select it and you ll see the first set of options available in the General Profile Settings category 2 in Figure 25 Here you can rename the profile to something that will help you remember it Under the Channel category 3 in Figure 25 you can select whether this is an IP connection BRIC normal a modem based connection which uses the telephone line rather than the Ethernet jack or IP Multicast a method to deliver audio to multiple locations Note It s important to define the channel of a profile before moving on to other op tions since the choices in the subsequent sections will vary in this choice Make sure to press Apply in order to confirm your selection GID CHEIID o ACCESS GD GD FW 2 8 p13 FLASH GUI 2 84 Connections Statistics Audio Metering Profiles System Settings PROFILE PROFILE SETTING SETTING ADJUSTMENT a 5 Sanne Gansta General Profile Settings oa gt SWAT Dau Local These settings apply to the whole profile HQ2 Default gt Remote HG2 Stereo Default ULB Default 3G PROFILE NAME 2 SE eme E BGAN CHANNEL BGAN AAC ELD BRIC Normal X Fotz AAC Mono BRIC Normal lt _ lt 3 AAC Stereo HTP HE AAC Mono z Multicast denotes factory profile ire lt gt denotes default profile Standard RTP x Set Default Add New Profile Copy Profile 4 Remove Profile Apply Set to Defaults _ Show advanced options UATE Send Figure 25 Creating a New Profile ACCESS Prod
7. Winston Churchill Winston winston ww2 co uk 876 987 3456 Figure 44 Switchboard Users List In some situations it might not be desirable for every codec in your fleet to see the Switchboard status of every other codec To help filter what s displayed on a codec s interface Switchboard has implemented the concept of Contact Lists Contact Lists contain a subset of your codec fleet on your account You can create multiple Contact Lists that consist of different subsets With the exception of Shares discussed next only units within your Switchboard account may be assigned to Contact Lists Contact List Units City Hall ACCESS Rac Master Control SS Ra 40 6 00 01 c0 04 a8 ae EE Weather Chick A SSF Kabul office SS Portabl Figure 45 Switchboard Contact Lists ACCESS Product Manual SHARES By default a master Contact List is created that contains all codecs on your account And by default every codec in your fleet uses the master list So if you re not interested in segregating codecs on your account the default configuration will work fine You can create multiple Contact Lists each with a subset of your codecs and save them on the Switchboard server You then have the ability to assign these lists to your codecs This will reduce the number of devices displayed on that unit to the codecs on the Contact List This is an important point Assigning a Contact List to a codec determines what gets displ
8. gives an indication of the same values instantaneously as well as the total amounts of incoming and outgoing data in bytes for the current connection This information can be helpful when operating on data networks with per megabyte transfer charges If you do not have an unlimited data plan you may want to keep track of overall data usage and optimize your connection profile for the most efficient transfer settings For additional information on choosing encoding algorithms and other ACCESS settings see Section 16 ADVANCED Topics These totals reset once the connection is closed Network tats Configure Remotes Stats Configure CN Graph Channel Stats Total Receive Rate 45 6 kbps Total Transmit Rate 45 6 kbps Total Receive 39 0 KB Numeric Total Transmit 38 0 KB 0 0kb 46 8kb Tx 0 0kb BRIC Normal r C Show Averaged Statistics eric me l C Show Averaged Statistics 3 7 EI Menu Arrows Enter Navigation 3 my 3 EI ss Menu Arrows Enter Navigation 3 my j Figure 10 Channel Stats in Graph Format Figure 11 Channel Stats in Numeric Format 24 ACCESS Product Manual The Peer Stats display is shown in Figure 12 The top graph represents the work of the Jitter Buffer Manager The area of most interest is the light blue area as shown in the diagram which illustrates a spread of jitter values referenced to the current playout pointer over the last second If this area covers a
9. lt HQI Defauit gt HQ2 Default HG2 Stereo Default ULB Default 3G E Transmit On Off 3G AAC ELD BGAN General Y Local Connection Timeout Encoder F Congestion Avoidance UDP Reliability Audio Metering Profiles SETTING ADJUSTMENT Transmit On Off Transmit audio to connected remote CURRENT On DEFAULT On System Settings BGAN AAC ELD gt Remote POTS AAC Mono don AAC Stereo HE AAC Mono HE AAC Stereo denotes factory profile lt gt denotes default profile Set Default Add New Profile Copy Profile Remove Profile Show advanced options CHAT Send Figure 49 Transmit On Off in the Profiles Tab In the multi streamer as caller model two different profiles will be built on ACCESS A The first profile labeled Multi Duplex will be defined as a normal full duplex ACCESS connection The encoder to be used will be selected in the Local Encoder section and the stream desired in return will be defined in the Remote Encoder section The second profile is called Multi Simplex and in this profile the Remote Transmitter is turned Off Most other selections in this profile are irrel evant User A will define remote connections for ACCESS B C and D He will assign the Multi Duplex profile to ACCESS B and Multi Simplex profile to the others He will then establish a connection with ACCESS B first fol lowed by C and D In model number 2 where the ser
10. outgoing requests may be made on UDP ports 3478 and 3479 By default the device serves as an SSH host on TCP port 22 Only SSH clients with an authorized DSA key can access SSH services on the device Other forms of authentication are disabled This key is kept confidentially by Comrex for factory diagnostics only SSH services may be disabled completely via the user interface Under normal operation the device is controlled by a networked computer via a web page served from the device on the standard HTTP port 80 TCP This page requires Adobe Flash Player on the browser and the Flash plugin establishes a TCP connection back to the device on the XML port 8080 Both of these ports are required for the remote UI to function and the port assignments are configurable These services may be disabled by the user interface but this will disable both the remote GUI and the on line updater TCP Port 8080 is also used by the optional Remote Control software The device will respond to standard ICMP requests ACCESS Product Manual APPENDIX C DECODE SIDE SETTINGS ONLY ENCODE SIDE SETTINGS ONLY Usinc ACCESS on UNIDIRECTIONAL NETWoRKS Under most circumstances ACCESS requires an IP path in both directions for successful connections even when audio is being sent only one way For networks that provide data only in one direction it is possible to use Standard RTP mode to establish and maintain these links This section describes how
11. see descriptions Voltage 90 264 VAC 50 60 Hz Power 50 Watts 120 VAC 60 Hz 65 Watts 240 VAC 50 Hz Dimensions 19 W 48 3 cm 9 75 D 24 8 cm 1 75 H 4 45 cm Weight Unit alone 8 6 lb 3 9 kg Shipping 15 lb 6 8 kg with all peripherals and packing 119
12. t any way to retrieve a forgotten password it must simply be changed in each ACCESS ACCESS Product Manual CONNECTING TO A SPECIFIC PORT GD GD ACCESS FW 2 8 p10 FLASH GUI 2 7 1e Connections Statistics Audio Metering Profiles System Settings SYSTEM SETTING a H SETTING ADJUSTMENT H System Settings Security Settings A traversal Sener Security settings such as passwords are configured here Contact Closures Aux Serial Settings E Security Settings gt BRIC Normal Settings CONNECTION PASSWORD 1 gt Modem Settings e gt N ACIP SIP Settings GUI PASSWORD MEnable remote SSH access __ Show advanced options Ft ee SC Apply Set to Defaults Software Licensing CHAT Send Figure 29 Connections Password in the Settings Tab BRIC IP connections and all IP traffic use a concept known as ports to differentiate between different applications on the same computer A port is simply a number contained in the IP header but it can be treated as a physical opening in and out of your computer Most firewalls function by opening the network to traffic with only specific port numbers Each IP connection has a source and destination port Under most cir cumstances the source port is unimportant but the destination port can be key Certain incoming ports can be firewalled to outside traffic and in the case of several ACCESS behind a router sharing a single public IP ad dress the only way for them all to take incomin
13. user packets are determined by the Internet Service provider so if there is contention heavy user data may have an affect on decoder performance Under most circumstances ACCESS will be sharing a network with an USB based network based attached to its USB port and distributing data to other users via Ethernet In this configuration you will need an Ether net switch between ACCESS and the computers getting the data Alternate ly if only one computer will be connected an Ethernet crossover cable may be used between ACCESS and the computer This type of connection is shown in Figure 51 ACCESS is using an USB based device to connect to the Internet and using its Ethernet port to share the IP connection with a laptop computer via a crossover cable ACCESS connection to the Internet via the USB based network device SS SS Connection from the computer to the ACCESS Ethernet Jack using an Ethernet crossover cable Figure 51 Gateway Connection 87 COMREX CORPORATION GATEWAY MODE 88 Gateway Mode involves having two networks active and enabled on ACCESS The Internet side usually an USB based network device which is used to connect to the world at large and the shared side usually Ethernet which is used to connect with other computers Configuring for Gateway operation may only be done through the Console Connection Interface The only step to Gateway Mode is set ting up your shared network side with the factory d
14. ELD EE SE codec P DEFAULT BGAN AAC ELD rors POTS codec AAC Mono AAC Stereo Poe HE AAC Mono Stereo POTS HE AAC Stereo denotes factory profile lt gt denotes default profile Set Default Add New Profile Copy Profile Remove Profile Apply Set fo Default _ Show advanced options CHAT Send Figure 33 POTS Codec vs POTS Stereo Mode in the Profiles Tab In order to use POTS Stereo Mode special configuration must be done on each end of the link Once an ACCESS is set for incoming POTS stereo con nections normal mono POTS codec compatible calls can not be received until the settings are changed back Outgoing unit settings usually the field unit The outgoing ACCESS will dial the phone call but a profile for the outgoing call that specifically uses POTS Stereo Mode must be built This is done by creating a new pro file in the Profile Manager Select Channel under Global Settings and then Modem for the outgoing channel Under Local Settings choose a Modem Mode of Stereo POTS Once the profile with these parameters is built it can be named and as signed to any outgoing remote that uses a phone number rather than an IP address as its destination Additional profiles may be built utilizing the normal POTS codec modem mode if desired You can then build two remotes to the same phone num ber one using your stereo profile and one using your legacy compatible POTS codec profile ACCESS Product Man
15. ELD The deciding factor between these algorithms is digital bandwidth BRIC ULB uses very little BRIC HOI and AAC ELD optional upgrade require more 3 Is audio quality the paramount concern AAC or HE AAC op tional upgrades are the best choices for applications that need excellent audio quality If delay is also a concern consider AAC ELD optional upgrade If you are running on an unconstrained net work and without the optional algorithms Linear PCM would be a good choice 4 Am I running on a constrained network If your Internet pipe is subject to being throttled use BRIC ULB for mono voice audio and BRIC HQ2 for stereo voice or music These algorithms offer the absolute highest quality in exchange for extremely low network bandwidth If you have the optional AAC upgrade HE AACv2 can also be a very effective low network utilization option 5 Do I need to deliver two unrelated audio signals to the same location BRIC HQ1 AAC HE AAC and AAC LD optional upgrade offer Dual Mono options that allow uncorrelated signals such as dual language broadcasts to be combined to a single outgoing stream Note It isn t possible to send one stream to location A and one to location B However it is possible to send the combined stream to locations A and B and have them tap only their respec tive channels although this can be a confusing solution subject to operator error ACCESS Product Manual Comparison Chart for A
16. IP Multicast users will be familiar with the basic concepts of setup and operation of the network so we will focus on how to configure ACCESS for Multicast mode To set any remotes to Multicast you must first create a profile for either a Multicast Sender or a Multicast Receiver on the Profiles Tab GHD Ga E ACCESS GID Gaz FW 2 8 p13 FLASH GUI 2 8a Connections Statistics Audio Metering Profiles System Settings PROFILE PROFILE SETTING SETTING ADJUSTMENT New fronie ise General Profile Settings lt HQ1 Default gt gt Local e These settings apply to the whole profile HQ2 Default gt Remote HQ2 Stereo Defauit ULB Default 3G 3G AAC ELD BGAN BGAN AAC ELD POTS AAC Mono AAC Stereo HE AAC Mono denotes factory profile lt gt denotes default profile Set Default Add New Profile Copy Profile Remove Profile Show advanced options CHAT Figure 50 Multicast Selection PROFILE NAME New Profile CHANNEL Multicast BRIC Normal HTTP Multicast Modem Standard RTP Send in the Profiles Tab ACCESS Product Manual SETTING UP A MULTICAST REMOTE TIME TO LIVE CHANGING PORT NUMBERS FOR MULTICAST As shown in Figure 50 when you define a new profile you have the op tion to choose Multicast as the profile type Multicast profiles have fewer options than other profile types and some of the available options will have no effect e g setting an encoder type on a Multic
17. Once a profile is defined it will be available on the Connections Tab to be assigned to any defined connection Building and managing profiles as well as the advanced profile options on the Console Connect Interface are similar to using the Web Based Interface Please refer to the Prories Tag BUILDING A PROFILE and ADVANCED Prorite Options Web based Interface section for complete details Network Remotes Stats Configure Profile Settings New Profile Global Settings Profile Name New Profile Channel BRIC Normal Visible Visible Local Settings Connection Timeout 60 i i Encoder A1 BRIC HQ1 Mono i Transmit On Off On Congestion Avoidance Not Enabled i UDP Reliability Not Enabled EL Remote Settings Connection Timeout 60 Encoder Follow local encoder Transmit On Off On Congestion Avoidance Not Enabled i UDP Reliability Not Enabled _ Show Advanced Settings g Q Fl Menu Arrows Enter Navigation Figure 17 Profile Settings for a New Profile ACCESS Product Manual SYSTEM SETTINGS The System Settings Tab defines parameters that are not specific to a particular remote connection Examples are how incoming POTS and IP calls are handled global modem settings and how the contact closures are assigned The System Settings Tab is shown in Figure 18 The Systems Settings Tab has nine categories System Settings Aux Se rial Settings Security Settings BRIC Norma
18. STUN This can be enabled in Comrex codecs and essen tially allows for the codec to learn what its public IP address is It does this by contacting a STUN server out on the Internet the default one is main tained by Comrex and simply asking If this option is enabled the codec itself will handle the address switcheroo Be aware of the dreaded battling workarounds issue In our simple de scription we left out the fact that ports are being translated by the router as well as IP addresses If the ALG enabled router receives an unexpected result in the SIP address field as it might if using STUN it may not trans late ports as expected and it s likely that the call will fail When in doubt the best technique is to try a SIP call with STUN turned off and if the re turn channel fails try enabling STUN Fix of Last Resort Finally there s a brute force option available on Comrex Codecs when STUN ports are blocked by a firewall or it can t be used for some other reason Under Advanced System Settings a field is available called Public IP Override Any address put into that field will be pasted into the ad dress SIP field So if you know what your public IP address is can be gotten from many websites via a browser you can manually paste it here Keep in mind this is often subject to change over time and obviously if you use a different network so it s important to remember this change has been made on your codec ACCESS
19. URL setting allows you to change the default homepage for the ACCESS Web Browser ACCESS has many administrative features that are often unnecessary for the casual user Restricted User Mode allows you to hide options that would confuse non technical users allowing them only to connect and disconnect calls enable and disable available networks and change the audio settings Restricted User Mode is enabled and disabled using the checkbox It is not password protected and can easily be disabled by any user Network Remotes Stats Configure User Interface Configuration F2 Key Behavior Cycle Through Screens M Web Browser Home URL http www google com _ Restricted User Mode ei Q Fl Menu Arrows Enter Navigation Im Figure 19 User Interface Tab ACCESS Product Manual CALIBRATE TOUCHSCREEN RESET CONFIGURATION ACCESS Rack supports connection of some VGA style touch screen interfaces Contact Comrex for tested models In a mobile environment this can allow a user friendly interface without use of a PC or keyboard USB style touchscreens must be attached before booting the ACCESS Rack and the user will be presented with a calibrations screen upon first connection Once this calibration is done the screen may be recalibrated by using this option If no touchscreen is detected this option is not available This option will restore your ACCESS software to factory def
20. Whenever ACCESS is connected to a data constrained network e g wireless it is strongly recommended that these meters be Off especially if the Web based Interface on the constrained network will also be accessed via the wireless network e g from the studio end The bandwidth requirements to drive the meters may affect performance of the audio codec The Metering Quality option which is defaulted to low adjusts how often the meters are updated better networks can support higher quality settings Refer to 1 in Figure 23 ACCESS GID Gaz FW 2 8 p13 FLASH GUI 2 84 V Analog Meters Digital Meters dBu Scale dB FS Scale _ Status Bar Meters Waveform Display METERING QUALITY Low Quality CHAT Send Figure 23 Audio Metering Tab 38 ACCESS Product Manual PROFILES TAB ACCESS provides a powerful set of controls to determine how it connects The Profiles Tab allows you to define one or more profiles to assign to outgoing remote connections It s often not necessary to define any pro files since ACCESS ships with a set of default profiles that cover most users But this tab allows you to build custom profiles to allow for differ ent encoders in each direction special POTS coding modes and special options for jitter buffer management Keep in mind that these profiles are useful only for connections initiated from the local ACCESS Incoming con necti
21. a telephone line Excessive RENs on a telephone line may result in the devices not ringing in response to an incoming call The sum of RENs should not exceed five 5 0 To be certain of the number of devices that may be connected to a line as determined by the total RENs contact the local telephone company The REN for the Comrex ACCESS Rack is 0 1 and is shown as the digits represented by in the product identifier US DXDMD ACCRK If the Comrex ACCESS Rack causes harm to the telephone network the telephone company will notify you in advance that temporary discontinu ance of service may be required But if advance notice isn t practical the telephone company will notify the customer as soon as possible Also you will be advised of your right to file a complaint with the FCC if you believe it is necessary The telephone company may make changes in its facilities equipment op erations or procedures that could affect the operation of this equipment If this happens the telephone company will provide advance notice in order for you to make necessary modifications to maintain uninterrupted service If trouble is experienced with the Comrex ACCESS Rack please contact Comrex Corporation at 978 784 1776 for repair or warranty information If the equipment is causing harm to the telephone network the telephone company may request that you disconnect the equipment until the prob lem is solved 111 COMREX CORPORATION 112
22. and choose Zephyr Xstream b Incoming Connections Zephyr Xstream sends an AAC stream to the ACCESS on UDP port 9150 These streams will be automatically decoded By default a return channel of AAC 96kb s mono is returned to the Xstream The return channel may be altered to any Xstream com patible mode in the Systems Setting section ACCESS that do not have the AAC upgrade applied will not create a return channel c Outgoing Connections ACCESS AAC Option required Build a profile using the Profile Manager on either the ACCESS Rack or Portable and select a Channel Mode of Standard RTP Then choose an Xstream compatible encoder for the outgoing call The Xstream will control what type of stream if any is returned to the ACCESS 3 Standard RTP This mode is set to receive a basic unformatted AAC stream within a standard RTP UDP structure At present this mode does not offer compatibility with other industry devices 114 ACCESS Product Manual APPENDIX B INFORMATION FOR IT MANAGERS The purpose of this appendix is to describe all open ports and services available on the Comrex ACCESS If a service is not mentioned here it is disabled by default The Comrex ACCESS is a device designed to move real time wideband audio over IP networks The main network interface is 10 100 10baseT Ethernet The device contains an optimized version of the 2 6 Linux kernel The IP parameters are set using a GUI that requires attachme
23. and you will remain incompatible with the other two types until you change it This setting has no effect on normal ACCESS BRIC POTS AAC functions which continue to operate as before 1 Luci Live This PDA PC based software allows real time streaming over IP links As of version 1 2 Luci Live includes AAC and HE AAC in addi tion to the default MP2 algorithm ACCESS can communicate with Luci Live only in Luci s AAC modes Note The free demo available from Luci does not incorporate the AAC functions you must have a licensed and registered copy to use AAC To communicate with a Luci Live device a Initial Setup This will define all Standard RTP connections to be Luci Compatible i ACCESS Rack On the System Settings Tab open the Stan dard RTP Settings option and choose RTP Compatibility Mode On the pull down box choose Luci Live ii ACCESS Portable Choose Configure then System Settings on the display Under Standard RTP Settings select RTP Compatibil ity Mode and choose Luci Live b Incoming Connections Luci Live sends either an AAC or HE AAC stream to the ACCESS on UDP port 5004 These streams will be auto matically decoded By default a return channel of AAC 56kb s mono is returned to the Luci Live product The return channel may be altered to any Luci compatible mode in the Systems Setting section ACCESS that do not have the AAC upgrade applied will not create a return channel c Outgoing Connections ACCES
24. as it does not feature the mandatory MPEG Layer II codec Aside from this ACCESS has been tested to be compatible with several other manufacturer s devices using encod ers supported by both products When using N ACIP SIP Compatible mode this is how the user interface describes EBU3326 ancillary data contact closures Switchboard TS Multi streaming and Multicasting are not sup ported Outgoing call profiles built with the NACIP SIP channel may lack some advanced options and can not be set for different encoders in each direction i e N ACIP SIP calls are always symmetrical 89 COMREX CORPORATION N ACIP SIP Moves UNREGISTERED MODE REGISTERED MODE SIP SERVERS SIP URIs 90 A function of placing a SIP style call is the ability to register with a SIP server This is a server that exists somewhere on the network usually maintained by a service provider Several free servers exist that can offer registration like Gizmo5 and Iptel ACCESS allows N ACIP SIP calls to be placed or received with or with out registration on a SIP server If registration is not enabled connec tions are made directly to the compatible device by dialing its IP ad dress just like in BRIC Normal mode Placing a call in Unregistered N ACIP SIP mode is simple just build a profile but instead of choosing BRIC Normal channel choose NACIP SIP This will make sure the call is initiated on the proper ports and with the proper signaling The m
25. con nection attempt will be made whenever the contact is triggered and will disconnect whenever the contact is released CC Connect Status This setting 4 in Figure 26b alters the perfor mance of output contact closure 4 Under normal circumstances the signal indicates a trigger of the corresponding contact closure input on the far end of the connection If this box is selected that function is no longer available and the signal follows the ACCESS front panel Ready light This signal will be valid closed when a valid connection is present and invalid open when no connection is present This allows you to set the parameters of the auxiliary serial data port provided on the ACCESS This port is always active during an IP connection and allows serial data transfer along the same path used for the audio data It does not remove any audio data the serial data is added to the packets and bandwidth is increased to support the additional data For this reason heavy use of serial data can affect overall codec performance Settings are available for Baud Rate Data Bits Stop Bits Flow Control and Parity Most users will leave the defaults of 9600 8 1 No Flow Control and No Parity Connection Password Allows you to define a password that must be attached to all incoming connections before they are accepted Units placing outgoing connections to you must know this password and apply it to their outgoing stream Leaving the field bla
26. following section describes how to enter local remotes into the product to dial them by IP address If you plan on using the Switchboard Traversal Server or take only incoming calls this step may not be neces sary For more on Switchboard Traversal Server see Section 10 The Connections Tab is the default setting for the Web based Interface as shown in Figure 21 In this tab you can program and save the names and addresses of any remote units you connect to This allows custom pro gramming of policy parameters for each remote and allows point and click connect and disconnect To add a remote ACCESS to the list simply click Store New Remote in the lower section An input box will appear allow ing you to enter a user name which can be anything and the IP address of the unit You will also need to choose a profile to use when connections to that remote are initiated To get started simply choose one of the de fault profiles provided we ll show you how to build your own later You may remove any stored value simply by highlighting and clicking Remove Stored Remote Stored remote addresses are saved to system memory where they will remain through power cycles The Connection Tab will also display IP and Status information of a re mote ACCESS when it has initiated a connection to you Their information will only appear while the connection is active By default three users appear on the list You may use any of these to test diffe
27. for more info on selecting encoders Transmit On Off This option determines whether the selected encoder local or remote is actually sending any data By default all encoders are turned on but there may be circumstances where one way operation is desired e g multi streaming as described in Section 12 Turning off the local encoder disables outgoing audio streaming and disabling the remote encoder disables incoming audio streaming Two options are available to help transmissions that are suffering from poor network performance There are encoder treatment options so the are applied to the local encoder the remote encoder or both BRUTE options require 2 7 or higher software on both ends of the link Congestion Avoidance Enabling this option allows the encoder to dynamically change the number of frames packet sent thereby reducing total data requirements In addition in most encode modes enabling congestion avoidance provides the system a license to step down toa lower encode data rate if desired This will happen automatically and with no audio interruption Step down congestion avoidance is not enabled in ULB HQ2 or Linear PCM modes 41 COMREX CORPORATION POTS SETTINGS SETTING UP ACCESS FOR USE ON POTS STEREO 42 UDP Reliability UDP the Internet protocol used by BRIC Normal connections does not have any inherent error correction capability UDP reliability adds an intelligent algorithm th
28. is designed to connect to a 9 pin PC serial port with a straight through M F cable RS 232 levels are used Table 4 Serial Port Pinouts DTR ToACCESS Ground Dep From ACCESS RTS ToACCESS CTS From ACCESS Rr Unused 12 ACCESS Product Manual SECTION 3 Hooxine Up ABouT NETWORK CONNECTIONS SETTING UP ACCESS NETWORK CONNECTIONS Settinc Up ACCESS At a minimum ACCESS will need an audio connection and a network connection Levels of all analog audio I O is OdBu 0 775V nominal This level will provide 20dB headroom before the clipping point Input audio is reflected on the front panel LED based peak meters Clipping is indicated by the Red LED on these meters ACCESS needs a network connection to be useful On ACCESS Rack the network connection is made via a standard 10 100baseT Ethernet connec tion on an RJ 45 connector In most ways ACCESS will look like an ordinary computer to this network In fact ACCESS contains an embedded computer with a Linux based oper ating system and a full network protocol stack ACCESS is perfectly capable of working over most LANs but there may be situations where a LAN is heavily firewalled subject to overloaded traffic conditions or have security concerns Better performance is possible if ACCESS has its own Internet connection Often it s worth the trouble to install a DSL line especially for ACCESS especially if the cost is reasonable Since there
29. make ACCESS work By clicking the Advanced Options box in the lower left of the Profile Settings screen the following Advanced Options will be available In addition to BRIC Normal and POTS ACCESS provides the ability to set up several other channel types The Advanced menu gives the option to use a different channel rather than the normal UDP RTP created in BRIC Normal mode Some explanation Internet IP packets come in two flavors TCP and UDP Most web browsing email and other computer based functions travel over the TCP protocol which inherently assures retransmission if a packet is lost and is therefore reliable UDP is optimized for real time applications and does not offer any guarantee of packet delivery Retransmission typically causes extra delay in an IP network and ACCESS is optimized to conceal an occasional lost packet so it makes more sense for ACCESS to use UDP for transmission under most circumstances But there are occasions where a network will treat UDP packets poorly Some examples are e Networks with high packet loss rather than jitter e Networks with very high security firewalls e Networks trying to discourage the use of VOIP functions In these circumstances it makes more sense to enable a TCP channel The result will usually be a more robust audio channel with a delay several magnitudes higher than an equivalent UDP channel Channel overhead is also raised so you will utilize a higher network bandwidth AC
30. server can automatically derive the reply address from the request and respond to it So the traditional four segment decimal address e g 70 22 155 130 is completely obscured to the user Even if you know your IP address it s quite possible that address will change over time This is because the vast majority of Internet users establish their addresses via DHCP a protocol whereby a server maintained by the ISP will deliver one of their available addresses to the client on initial connection That address is leased from the server for a particular time period and after the lease expires the server is free to change it The commonly encountered NAT Network Address Translation router adds to the confusion making codecs even harder to find Most LAN based Internet connections as opposed to computers connected directly to ISPs actually negotiate with a local router containing its own DHCP server This router assigns the LAN computer or device a private IP address We ll cover more about the challenges of connecting codecs behind NAT routers shortly but one of the hassles they add is that the private IP address delivered to the codec and the only address of which the codec is aware has no bearing on the public address seen from the Internet As shown in Figure 35 in extreme scenarios several layers of address locality can be stacked assuring that the IP address assigned to your is several degrees removed from the public I
31. server you will get a download of the all other codecs in your group to your Remote List as shown in Figure 42 On the Web based Interface Switchboard TS entries are shaded as shown in Figure 43 Network Remotes Stats Configure TS Online Open gt Loopback 6 E Comrex Lab Voice LR Comrex Lab Music Ei POTS DI Andy s Portable 6 3 Dr Evil a Ei Master Control 2 EL J Secret Squirrel 3 JE Test Rack 134 6 tom s portable lm es Q F1 Menu Arrows Enter Navigation Kg EH Figure 42 Switchboard TS Remote List ACCESS Product Manual ACCESS GD GD FW 2 8 p13 FLASH GUI 2 80 Connections System Settings REMOTE ACCESS UNITS Name Address Current State Receive Status Profile Last State Transmit Status oe Loopback 127 0 0 1 not connected MNES Comrex Lab Voice 70 22 155 131 not connected ee Comrex Lab Music 70 22 155 132 not connected NNS ocou ACCESS Rack 74 94 151 150 9000 not connected REGISTRATION STATUS BRIC Link 74 94 151 149 9000 not connected MNES STATUS SIP STATUS Lab Music 70 22 155 132 9000 not connected ONLINE 200 OK PUBLIC IP ADDRESS 70 22 155 131 NAT TYPE L Open Store New Remote Remove Stored Remote Change Remote Settings CHAT Send Figure 43 Switchboard TS Entries on the Web based Interface In addition on the Console Connection Interface the type of NAT router that is detec
32. them if desired ACCESS Product Manual More Apout ACCESS RACK Wuart Comes WITH ACCESS RAcK ACCESS Rack incorporates all the features algorithms and services of BRIC as defined in the previous sections Its main function is to provide a robust high quality low delay audio link in full duplex over challenging IP networks like the public Internet To this end it provides an intuitive and attractive Web based Interface via web browser and a direct connect Console Connection Interface Using these interfaces you can select op erating modes check audio levels make and end connections and check network statistics of any connections you make While ACCESS is designed to handle most network challenges in its default configuration advanced options are available to allow customization of parameters that have effect on link stability and delay But wait There s more ACCESS is also a POTS codec It has a built in modem which can be set to make calls over analog phone lines directly to other units In this mode ACCESS can communicate with other ACCESS devices or with a range of previous generation POTS codec devices made by Comrex The following items are shipped with a new ACCESS Rack 1 ACCESS Stereo BRIC IP Codec Rackmount 1 6 Ethernet cable 1 6 Telephone cable 1 AC Power cord 1 Operating manual 1 Warranty card Please fill out and return COMREX CORPORATION SECTION 2 Figure 1 Rear Panel Diagra
33. they are no longer important to the user If the address should change the codec will re sync with the server from the new address and all will be updated Connections can be made by simply clicking on the correct name regardless of current IP address Network Remotes Stats Configure Directory Online Loopback Comrex Lab Voice ta Come Lab Music Dick Dastardly Boris Badanoff C Master Control 1 Master Control 2 Natasha E Fe Fe Fe a po o DR SS Figure 36 Switchboard TS Buddy List 69 COMREX CORPORATION 70 The other roadblock provided by the use of NAT routers is the inability to accept unsolicited incoming connections from the Internet In a general sense this function acts as a rudimentary firewall and is a net positive for security but it does cause headaches for codec users As shown in Figure 37 a router that receives a connection request doesn t have a clue where to forward that stream unless it has specific instructions programmed into it known as port forwarding This can work well for fixed installations but it s not always an easy task to obtain that kind of security access on corporate routers and forwarding functions are implemented differently on different hardware You can easily imagine the complications of obtaining or managing port forwarding on the LAN at each remote venue you would certainly encounter a high volume of grumpy I
34. to SBR for higher quality audio at low data rate I1 Mono I2 Stereo D Dual Mono allows independent programming to be sent on both L amp R channels 14 Stereo 256Kb 16 Mono 128Kb 17 Mono 64Kb J1 Mono J2 Stereo J3 Dual Mono allows independent programming to be sent on both L amp R channels J4 Mono 24Kb 98 ACCESS Product Manual Q Can I make ACCESS maintain an IP connection regardless of net work status A Yes First define your remote setting and apply a profile to it Next go to the System Settings Tab and pull down the menu labeled Always Con nect to Remote Once you select your remote here a connection to the remote will be established and remain indefinitely Q Can I get a remote indication that ACCESS is connected to some one A Yes Using the System Settings Tab you can re assign Contact Closure Output 4 to trigger whenever the ACCESS front panel Ready light is lit indicating a valid incoming connection The function of Contact Closure 4 will be changed in the following ways a Contact Closure 4 will no longer be available as an end to end signal b Whenever ACCESS detects a valid incoming stream it will trigger CC 4 and maintain it until all valid connections stop Q What steps should I take when I m having connection problems with ACCESS A There are several steps you can take to determine that cause of poor IP connection using ACCESS The first step is to determine whether the proble
35. to set that up The following setting applies to both codecs in the link encoder and decoder The codec has several compatibility modes under the Standard RTP channel mode The units default to a mode that is compatible with the Luci Live PC based encoder This must be changed on both codecs 1 On the ACCESS Rack enter the Web based User Interface and choose the System Settings tab On the ACCESS Portable choose Configure gt System Settings 2 Find the Advanced tick box and check it 3 Find Standard RTP Settings and choose to edit the RTP Compatibility mode 4 Change this setting to Standard and click Apply or Save on ACCESS Portable Also under Advanced Standard RTP Settings find the Return Channel Enable entry Disable the return channel and click Apply or Save on ACCESS Portable This will make sure that no channel will be set up in the direction to the encoder Obviously connections of this type must be established from the encoding side of the link So you ll need to build a new Profile that uses the Standard RTP channel mode under the Profile Editor Choose your outgoing encoder along with any other special attributes in the profile editor Name the Profile something descriptive like Simplex Next create your outgoing remote entry in the address book Apply the new profile to that entry Any connection made with that entry will connect in a unidirectional fashion 117 COMREX CORPORATION FULL TIME OR
36. 04 Ring Count For Incoming POTS calls this setting determines how many rings to allow before answering Max Modem Rate Min Modem Rate These settings constrain the modem and instruct it not to connect higher than the Max or lower than the Min This is valid for incoming and outgoing POTS calls Extra Modem Init This option will allow the entry of special initialization strings to be sent to the internal modem before a call is placed These strings can change things like country of operation dial tone and ring cadence frequencies and other phone line based parameters These settings offer several modes that allow compatibility with specific IP coding devices For complete details please review the JP ComPATIBILITY appendix of this manual For information on the N ACIP SIP Settings please see Szecz1on 16 MAKING N ACIP SIP COMPATIBLE CONNECTIONS ACCESS Product Manual TCP SETTINGS RTP IP Port Port used for audio transfer during N ACIP SIP mode Since this port info is transferred during the negotiation process it can be changed without breaking compatibility Note that RTSP data is always sent and received on the port one address higher than this Public IP Override Enable this in an environment where ports have been forwarded through a router to the ACCESS and a N ACIP SIP connection is desired The SIP protocol is assuming no ports are forwarded and may have trouble connecting without this function en
37. 131 me _ Outgoing request made Response direct to public IP address Cable DSL Modem Figure 3 Direct connection to Internet USERs connect to the Internet via the NAT router s assigned private IP addresses NAT router connects to the Internet via a single public IP address ex 208 37 242 6 and routes this to multiple private IP addresses which it assigns to users ex 192 168 0 37 User A ACCESS Rack NAT Router ex 192 168 0 38 User B laptop Server connects to the Gelee Internet via web address ex 70 22 155 133 User C laptop USERs communicate with SERVER X via the NAT router which translates information between public and private SERVER X IP addresses Figure 4 Connection to Internet via subnet or LAN 14 ACCESS Product Manual DYNAMIC Vs STATIC ADDRESSING To have the ability to make connections normally without using the traversal functions of the Switchboard Traversal Server Switchboard TS one of the ACCESS in the link should be connected to a public IP address This can be achieved several ways 1 ACCESS can be the only device connected directly to its Inter net link or it can share an Internet link that provides more than one IP address 2 ACCESS can be connected behind a NAT router which can be programmed to provide public Internet access to it through port forwarding But for now well assume you have a way to set up at least one en
38. 2 155 131 Not CONN ip ADDRESS OR PHONE NUMBER 9787841700 Comrex Lab Music 70 22 155 132 not CONN CONNECTION PASSWORD HE AAC Stereo POTS Test Line 9787841700 not conn SCH DETDA POTS Local d SS RERAN BACKUP REMOTE D DROP 2 No Backup H WATS at 3 Automatically fall forward Cancel OK T z z gt lt Store New Remote Remove Stored Remote Change Remote Settings CHAT _ gt j Send Figure 31 Backup Fall Forward Functions in the Connections Tab 59 COMREX CORPORATION Fatt FORWARD FUNCTION Backup FALL FORWARD LIMITATIONS 60 To enable an automatic backup both the primary and secondary remote connections must first be defined and assigned profiles Next select the primary remote and click Change Remote Settings On this pop up choose the pull down menu labeled Backup Remote 2 in Figure 31 and select the backup for this primary connection By selecting the Automatically Fall Forward function in this pop up 3 Figure 31 you will enable ACCESS to monitor the primary IP connection while the backup is active If the primary is restored and is detected to be valid for the timeout period the backup will be disconnected and opera tion will revert to the primary The Backup Fall Forward functions have the following limitations 1 Only IP connections can be designated as primary IP or POTS connections can be backups 2 Fall Forward does not work when the POTS backup is the same phys
39. 4 7 operation is initiated in the System Settings Tab using the Console Connection Interface this is found in the Connections section of the System Settings menu The field labeled Always Connect To Remote offers a pull down menu of all available connections Setting this value to one of your pre defined connections results in configuring the unit for 24 7 operation to that remote No configuration is necessary on the remote side ACCESS has another option for persistent connections When building a remote entry a field is available for backup options one of those options is Keep Retrying This Remote mode In a similar fashion using this mode will disable the connection timeout setting and keep a persistent connection The difference is that the Disconnect function still works and the connection will not be reinitiated on a power up This mode is meant for users who are making temporary connections but do not want the system to time out and disconnect in the event of network failure ACCESS GD GD FW 2 8 p13 FLASH GUI 2 80 Connections Statistics Audio Metering Profiles System Settings SYSTEM SETTING SETTING ADJUSTMENT E System Settings F Traversal Server System Settings e Unit name and auto connect are configured here El Contact Closures Aux Serial Settings Security Settings gt BRIC Normal Settings UNIT NAME gt Modem Settings Lab Voice gt N ACIP SIP Settings ALWAYS CONNECT TO REMOTE Do no
40. 5 which would signify an address with the Multicast Block with a TTL of 255 which is the max value available The default port of UDP 9000 may also be changed on Multicast remotes The port number is assigned in the usual way directly after the IP address preceded by followed by the TTL As an example the IP address of a Multicast Sender on port 443 with a TTL of 100 would read 224 0 2 4 443 100 85 COMREX CORPORATION SEcTION 14 Decopinc A HTTP STREAM SIMULTANEOUSLY CONNECTING ACCESS AND STREAMING 86 STREAMING SERVER FUNCTION ACCESS has the ability to act as a streaming server delivering AAC and HE AAC to compatible PC based media players Currently tested media players include WinAmp VLC and Windows Media Player with Orban CT HE AAC plug in By default streaming server functionality is turned off To enable it go to the System Settings Tab of the User Interface and choose HTTP settings option Under the first option set Accept Incoming Connections to Enabled Next you will need to choose an encoder for use by the streaming server Only the encoder choices that are compatible with the players listed are shown in this menu Choices span between a mono audio feed at 18 kb s up to a stereo feed at 128 kb s Keep in mind multiple streams will require this bandwidth along with around 25 overhead for each stream The Genre Info URL and Public options may be set for anything or left alone These opti
41. ACCESS Stereo BRIC IP Copec You ll be seeing me from time to time throughout this manual to point out ACCESS advanced topics Feel free to ignore these sections as the default settings provide good performance for most users TABLE OF CONTENTS SECTION JI INTRODUCTION vissvertercdovtsteatessetedetiaartvdedadeeveniedceasesdtedenseseeessveurucetiteneeesescds 7 E EE ee ee ER EEN MORE ABOUT ACCESS Rack H EE WHAT COMES WITH ACCESS Ruck D SECTION A Kack DIAGRAMS AND INSTALLATION 00 ccccececsececcucnscnseceseeeneessseenscesaeeneneenenes 10 EE REAR PANEL DIAGRAM AND DESCRIPTIONS e LO G d FRONT PANEL DIAGRAM AND DESCRIPTIONS e LL d etetk dee gebei IMONOWS STEREO sccssesveesceavtecasictan sentes aiai nee seu LL EEN PINOUIS e EE E EEN PINOUTS CONTACT CLOSURE e LD ORTEN DETA PINOUTS EK LZ SECTION 7 SETTING UP AGGESS EE 13 E EEE TIOORING EE E EE ABOUT NETWORK CONNECTIONS e LD deens eege age SETTING Up ACCESS NETWORK CL ONNFCTHONS e LD EE DYNAMIC VS STATIC ADDRESSING e LD SECTION A aaeeea GAINING ACCESS TO ACCESS VIA THE CONSOLE CONNECTION INTERFACE 1 1 00000000 17 SEEE EEA Top AND BOTTOM NAVIGATION Dags L7 ree INETWORK TS LD edd SE DEEN ETHERNET PORT SET UP e LOD DEE POTS MODEM Arr 20 REEERE EEREN UE A EE EE Nee Ee ee gue E STATS E ceases ssn seceakscarcccsasaaadedesasunascaavadayseaaseasaxdsaaanaitestadeaseviaseeld EEN ER AUDIO L EVEL E LO deeg CONFIGURE TAB cic Stegen Edge RA Ee EE SECTION D sinies C
42. CCESS Codecs Required Coding Audio Bitrate Delay Bandwidth Al Mono A2 Stereo A3 Dual Mono allows independent programming to be sent on both L amp R channels A4 Mono 24Kb restricted to 24 kbps coding rate B1 Mono B2 Mono 12Kb reduced bandwidth with fewer coding artifacts B3 Stereo B4 Stereo 12Kb reduced bandwidth with fewer coding artifacts B5 Stereo 24Kb C1 Mono lowest bitrate of any BRIC algorithm F1 Mono F2 Dual Mono F3 Mono F4 Dual Mono K1 Mono K2 Dual Mono K3 Mono K4 Dual Mono VoIP G 711 and G 722 coding algorithms for compatibility with SIPstyle VoIP phones X1 G 711 a law X2 G 711 p law X3 G 722 97 COMREX CORPORATION Comparison Chart for AAC Codecs Required Coding Audio Bitrate Delay Bandwidth D1 Mono D2 Stereo D3 Dual Mono allows independent programming to be sent on both L amp R channels D4 Stereo 128Kb D5 Dual Mono 256Kb allows independent programming to be sent on both L amp R channels D6 Mono 56Kb D7 Mono 96Kb D8 Stereo 160Kb E1 Mono E2 Stereo E3 Dual Mono allows independent programming to be sent on both L amp R channels G1 Mono 18Kb G2 Stereo 24Kb adds Parametric Stereo to SBR for higher quality audio at low data rate G4 Stereo 32Kb adds Parametric Stereo to SBR for higher quality audio at low data rate G3 Stereo 48Kb adds Parametric Stereo to SBR for higher quality audio at low data rate G5 Stereo 56Kb adds Parametric Stereo
43. CESS Product Manual ADVANCED CHANNEL OPTIONS ADVANCED ENCODER OPTIONS In addition to TCP there are several other advanced channel modes HTTP ACCESS has the ability to act as a streaming server delivering AAC and HE AAC to compatible PC based media players Normally in this mode connections are requested on an incoming basis so no outgoing profile setup is required But ACCESS also has the ability to initiate a stream to a Shoutcast compatible server in order to distribute the stream to users Only in this instance should a profile be set for HTTP Multicast Should only be used to initiate IP Multicast connections not for use on the Internet See Section 13 for more on Multicast connections Standard RTP This setting is used in the unusual scenario where the network is viable in only one direction Standard RTP has the ability to send and receive streams without any status information being relayed between the codecs When designating Local and Remote options for a normal BRIC or TCP channel several new categories will appear Some of them address the encoder and some address the decoder Most of the Advanced Encoder options alter the relationship between frames and packets In this context a frame is the smallest chunk of encoded audio that can be extracted from the encoder For the lowest possible delay this frame is wrapped into its own packet and sent into the network The following advanced option affect t
44. Gateway ALG then enabling this option can fix the issue Essen tially the router will get smart enough to read your SIP handshake find the outgoing address field and replace it with your public IP This is a pretty slick solution but there may be environments when you are not aware whether this option is supported on your router or have the ability to en able it So on to solution two Another technique for working around the SIP Router issue is by using a protocol called STUN This can be enabled in Comrex codecs in the Ad vanced N ACIP SIP options and essentially allows for the codec to learn what its public IP address is It does this by contacting a STUN server out on the Internet the default one is maintained by Comrex and simply asking If this option is enabled the codec itself will handle the address switching Be aware of the dreaded battling workarounds issue In our simple de scription we left out the fact that ports are being translated by the router as well as IP addresses If the ALG enabled router receives an unexpected result in the SIP address field as it might if using STUN it may not trans late ports as expected and it s likely that the call will fail When in doubt the best technique is to try a SIP call with STUN turned off and if the re turn channel fails try enabling STUN Finally there s a brute force option available on Comrex Codecs when STUN ports are blocked by a firewall or it can t
45. HQ2 has stereo modes which utilize a parametric stereo effect so it is not possible to send independent audio over the L amp R channels The channels must be a related ste reo image Use BRIC HQ1 or AAC LD when Dual Mono is required e Audio Bandwidth BRIC HQ2 default modes utilize a 32 kHz sampling rate to deliver 15 kHz audio fidelity BRIC HQ2 12K modes utilize a 26 kHz sampling rate to achieve a 12 kHz audio fidelity Because the data rate is the same between the two modes BRIC HQ2 12K can be considered to sacrifice some slight high end fidelity in exchange for overall lower audio coding artifacts 79 COMREX CORPORATION BRIC ULB ULTRA Low BITRATE LINEAR PCM FLAC G 711 80 This encoder decoder provides 7 kHz voice audio transmission with ex tremely low delay and extremely low network utilization Due to its low digital bandwidth it is considered to be the most robust mode for use on constrained networks Here are some of the details of BRIC ULB e Low Delay BRIC ULB uses a 20mS audio frame with an overall encode decode time of around 75mS This makes BRIC ULB a good choice for real time interactive applications s Low Digital Bandwidth BRIC ULB has a data rate of around 12 kbps allowing it to travel over very low speed networks Also since BRIC ULB is so efficient error correction may be added in many situations without congesting the network e Vocoder BRIC ULB relies on a voice based vocoder
46. IA EIAS 968 Telecommunications Tele phone Terminal Equipment Technical Requirements for Connection of Terminal Equipment To the Telephone Network July 2001 AW oH Thomas O Hartnett Vice President Comrex Corporation Note This equipment has been tested and found to comply with the limits for a Class A digital device pursuant to part 15 of the FCC Rules These limits are designed to provide reasonable protection against harmful in terference when the equipment is operated in a commercial environment This equipment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instruction manual may cause harmful interference to radio communications Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his Own expense 109 COMREX CORPORATION EC DECLARATION OF CONFORMITY FOR R amp TTE DIRECTIVE 110 We Manufacturer s Name Comrex Corporation Manufacturer s Address 19 Pine Road Devens MA 01434 hereby declare on our sole responsibility that the product Comrex ACCESS Rack Digital Audio Codec to which this declaration relates is in conformity with the essential require ments and other relevant requirements of the R amp TTE Directive 1999 5 EC This product is compliant with the following standards and other normative documents European EMC Dir
47. ITY D esierseiieiiiennsiinenieanen i 2D EES ege EAA BRIC HO2 HIGH legt eege geess egeah A deeeek eege een LI Se REES BRIC ULB U11RA LOW BITRATE ossee OO shsealedivdossdeahasoss LINEAR BECH scsiseceosscaceeceacedies d e dadd Eege eege Eege Eege hee e lest Seeerei ege OO Gedeelt GTI EE e the ee ee Mt edit ee eege EE dees Ais deed eet eege ead dg TIE AAG E e EEEE EES HEAACV2 snevre e Ee AACD EE GE e AAC BED EE SECTION JN MULS TREAMING edd SNE aE AEN EEEREN EE ERANA ERAEN EE ARAETA 82 SECTION 13 n IP e E 84 EE IMUOLTICAST PROFILES eege ASSEN a a desse degen eg OF dees SETTING UP A MULTICAST REMOTE 1 e OD See TIMEZTO LIVE nandana a ENKEN ERNREERAENEENKR ENKE EN uwen OO sixdedadvaragedessaness CHANGING PORT NUMBERS FOR Mrs OD SECTION J STREAMING SERVER FRUNCTION woes ccecesceeecesceceseuescsceescussessuseseseueseseussassuseueees 86 EE DECODING A HTTP Ara OO eege Zeie ege ged SIMULTANEOUSLY CONNECTING ACCESS AND STREAMING OO SECTION J GATEWAY e 87 Eege ABOUT GATEWAY OPERATION us e OF Ge CONNECTING AS A CATP d E E GATEWAY MODE ee e a a e SECTION Ip MakinG N ACIP SIP COMPATIBLE CONNECTIONS 0scsecceeseeceseeeseccueeeseussasenss 89 e MORE ABOUT EBI Z2eo e OD COMREX CORPORATION SECTION 17 SECTION 18 SECTION 19 SECTION 20 APPENDIX A APPENDIX B APPENDIX C APPENDIX D TABLE LISTING FIGURE LISTING EE LE KE EE EI ee ee EBU33206 SIP STUN anp IP COMPATIBILITY e LOL PAETA LICENSE AND WARRANTY DISCLOS
48. Internet Service Provider involved This is the only mode available to connect to other Comrex POTS codecs Because of the narrow bandwidth of dial up Internet connections use of POTS Codec Mode is strongly preferred over modem PPP Mode No options are available for Non PPP Mode The extra modem init string for this mode is done in the System Settings Tab the Advanced box must be selected in order for this option to appear PPP Mode allows the use of a dial up Internet Service Provider Configure your ACCESS with your ISP information The ACCESS will function like an IP codec over the link connecting to other ACCESS IP addresses PPP Mode should only be used when connecting to an Internet Service Provider via the modem In this mode you will need to enter the phone number user name and password settings provided by your ISP Once your ISP parameters are configured you may enable the modem and the call to your ISP will be dialed automatically This call will be maintained until the modem is disabled in the Network Tab 20 ACCESS Product Manual WEB BROWSER REMOTES TAB Connections in this mode are placed in the same way that normal IP connections are placed A remote connection must be built using one of the non POTS based profiles and the address must be an IP address PPP Mode depends on the modem connect rate and many codec profiles will not fit within the PPP channel We recommend use of the ULB Mode for most reliabl
49. LEDs R Receive will display 7 LEDs You can now assume that your ACCESS has the address of 192 168 1 007 Static IP Setting a Static IP requires that you enter some details into the ACCESS You will need to enter the following information via the Console Connection Interface IP address of the ACCESS make sure this has been provided by your ISP or that nobody else on your LAN is using this address e Subnet Mask A series of numbers that indicate the range of your LAN addresses If in doubt try 255 255 255 0 e Gateway Address The address of the Internet gateway on your account If in doubt try the first three number of your IP address with the last digit of 1 e g xxx xxx xxx 1 More details on how to input this information are contained in the next section ACCESS Product Manual SECTION 4 Top AND BOTTOM NAVIGATION BARS Gaininc Access To ACCESS via THE CONSOLE CONNECTION INTERFACE The use of the Console Connection Interface is required when configuring the IP parameters It also provides access to many of the features found in the Web based Interface We ll cover the Console Connection Interface here and the Web based Interface in later sections Using the Console Connection Interface requires that you attach a PS 2 or USB style keyboard and video monitor to the appropriate jacks on the rear panel of ACCESS Rack You may also attach an USB or PS 2 style mouse to make navigation easier When usin
50. Music M C Show Advanced Statistics Comrex Lab Music 1 1 Show Advanced Statistics J Fl Menu Arrows Enter Navigation gt m Ei zs Menu Arrows Enter Navigation eem Figure 12 Peer Stats in Graph Format Figure 13 Peer Stats in Numeric Format 25 COMREX CORPORATION AUDIO LeveL TAB The Audio Level Tab displays current input and output audio levels in a digital format The scale may be set for either dBu or dbFS as shown in Figure 14 Network Remotes Stats Configure Audio Level Metering eee e dbFs ee O dBu 60 54 48 42 36 30 24 18 12 6 0 hh S zz _ 7 Fl Menu Arrows Enter Navigation 3 Figure 14 Audio Metering CONFIGURE TAB The Configure Tab allows you to set up any global options on ACCESS as well as create custom profiles to determine the performance of outgoing connections Since these options are many they are treated individually in the next section 26 ACCESS Product Manual SEcTION 5 MANAGE PROFILES ConFiGURING ACCESS via THE CONSOLE CONNECTION INTERFACE The Configure Tab offers choices on two layers as shown in Figure 15 the first two commonly used functions followed by additional less often used functions Network Remotes Stats Available Profiles HQ1 Default i HQ2 Default HQ2 Stereo Default ULB Default 3G 3G AAC ELD Configure Manage Profiles System Settings User Interface Additional Configuration
51. No user serviceable parts are contained in this product If damage or mal function occurs contact Comrex Corporation for instructions on its repair or return Connection to party line service is subject to state tariffs Contact the state public utility commission public service commission or corporation com mission for information This equipment cannot be used on telephone company provided coin service If you have specially wired alarm equipment connected to the telephone line ensure the installation of the Comrex ACCESS Rack does not disable your alarm equipment If you have questions about what will disable alarm equipment consult your telephone company or a qualified installer ACCESS Product Manual APPENDIX A IP COMPATIBILITY IP compatibility using ACCESS firmware 2 3 and later offers several modes that allow compatibility with other IP coding devices These compatible modes rely on the AAC family of algorithms All ACCESS with firmware 2 3 are capable of decoding streams sent to them using these devices In order to encode streams that are compatible with these devices the optional AAC upgrade must be installed on the ACCESS Contact Comrex for more details The ACCESS is capable of encoding and decoding a choice of three dif ferent types of non ACCESS streams Standard RTP Luci Live and Zephyr Xstream The choice is exclusive i e you must set the ACCESS specifically for the type of stream you wish to be compatible with
52. ONFIGURING ACCESS VIA THE CONSOLE CONNECTION INvmRnach 27 ere geed MANAGE EE n E REENEN eege ARENS AER Ee See eg eg GI EE EREM ee aR a a aa aa a a D EE USER EE DL Ee CALIBRATE TO REENEN dENE SEENEN E ENEE ENNER TET OOD eege geg RESET CONFIGURATION e DD ACCESS Rack 2 8 FEB 2014 COMREX CORPORATION SECTIONG vassuueseee GAINING ACCESS TO ACCESS VIA THE WEB BASED INrERcCE 34 SECTION Je MAKING CONNECTIONS USING THE WEB BASED Ivmrkpck 54 SECTIONS gt annn OPERATING ACCESS IN A 24 7 ENVIRONMENT cccccccsccscccccescssesssecsscsassscuses 61 P E eege SETTING ACCESS FOR 24 7 Oprkamon e OZ SECTIOND semeen POTS Prarn OLD TELEPHONE SERVICE CODEC CONNECTIONS ccccseeeeeeeeeeeee seen 63 S POTS Copec SET UP FOR ACCESS Coupmgum OD ACCESS Product Manual Sisdaue Dla ege SETTING UP ACCESS FOR USE ON POTS Amt GL ege eege ds RATE DROP VS RETRAIN yicoxsecesvelebstevwes ds ociSedbes ovis sins Gases Sede heataness de OD Gd sab EEEE S TROUBLESHOOTING POTS CONNECTION e OO SECTION 1O seeen SWITCHBOARD TRAVERSAL SERVER OS 67 EE CONFIGURING SWITCHBOARD TRAVERSAL SERVER e JD Gage dE LOGGING IN AND SETTING UP THE SWITCHBOARD TRAVERSAL SERVER 73 Ee USING SWITCHBOARD IJ 4 Gees CREATING USERS ee deed 7 O E TATS CONTACT LISTS is sccsscensGeedseceessdats eaves a a aoaaa O POE EEA Ee SECTION JI ABOUT THE ALGORITHMS ois vissasics asses EEEE sede EEN NN SEENEN ANS Seadesaasededassees Ne 79 PE BKIC HOI HIGH QUAL
53. OTS Profile should work best Note When creating a profile you must designate the modem mode as POTS Codec rather than POTS Stereo in order to be compatible with legacy devices This is shown in Figure 33 To use ACCESS on POTS a normal analog telephone line must be con nected to the rear panel telephone line RJ 11 connector If possible try to obtain a true telephone company grade line rather than an extension from your digital phone system Under no circumstances should the raw exten sion from a digital phone system be attached to this port you will likely damage ACCESS your phone system or both To initiate calls from ACCESS simply create a remote connection with a telephone number as an address rather than an IP address in the Con nections Tab You must designate a POTS based profile for this remote 63 COMREX CORPORATION SETTING UP ACCESS FOR usE ON POTS STEREO 64 GID GEET KE ACCESS GID GD FW 2 8 p13 FLASH GUI 2 84 Connections Statistics Audio Metering Profiles System Settings PROFILE PROFILE SETTING SETTING ADJUSTMENT D Fy HO Default gt d General Modem Mode v oe Local This setting determines in which mode the modem initiates outgoing calls POTS codec mode HQ2 Stereo Default E Modem Mode default is compatible with previous generation Comrex POTS codec products while Stereo POTS ULB Default E Connection Timeout is only compatible with other ACCESS edi POTS cod codec 3G AAC
54. P address used for connections And of course each address in the stack is temporary and able to change at any time 67 COMREX CORPORATION 68 Internet Service Provider The IP address you receive from the network may be many layers removed from your Internet IP 70 22 155 131 Router 192 168 1 1 Client Computer 192 168 1 101 ACCESS 10 0 0 49 Figure 35 The Effect of NAT Before deployment of the Traversal Server the answer to this dilemma has been to assure that the codec located in the studio has a fixed public IP address By fixed we mean that the address is allocated exclusively by the ISP and that address is entered manually into the configuration of the codec and not subject to change This scenario works because IP calls are usually initiated from the field As long as the field unit can find the fixed address of the studio unit and send a stream to it a reverse channel can be created easily and automatically by the studio unit using the source information contained in the incoming packets Of course even in this scenario the studio IP address must be memorized or input into each codec individually The first function of the Traversal Server works around the dynamic IP address problem by acting as a Directory Server Codec users simply log in to the free server and are given an account name and password Once logged in it s a simple process to input the details of each codec owned On the co
55. Product Manual SEcTION 18 LICENSE License AND WArRanrTY DiscLosuRES FOR Comrex ACCESS MPEG 4 audio coding technology licensed by Fraunhofer IIS http www iis fraunhofer de amm Fraunhofer institut Integrierte Schaltungen ACCESS uses proprietary and open source software programs Some of the open source programs are licensed under the Gnu Public License GPL For more information on GPL see http Wwww gnu org As per the GPL source code for this software is available on request from Comrex on CD ROM or other electronic format To obtain this software please contact our support department at 1 978 784 1776 We retain the right to charge a small handling fee for distribution of this software ACCESS makes use of open source and or free software with the following copyright restrictions ncurses Copyright c 1998 1999 2000 2001 Free Software Foundation Inc See further Copyright notice below dropbear Copyright c 2002 2004 Matt Johnston Portions copyright c 2004 Mihnea Stoenescu All rights reserved See further Copyright notice below libxml2 Copyright C 1998 2003 Daniel Veillard All Rights Reserved See Further Copyright notice below Import code in keyimport c is modified from PuTTY s import c licensed as follows PuTTY is copyright 1997 2003 Simon Tatham Portions copyright Robert de Bath Joris van Rantwijk Delian Delchev An dreas Schultz Jeroen Massar Wez Furlong Nicolas Barry Justin Bradfor
56. RIC technology has been engineered not only to be robust enough for the Internet but usable in really challenging Internet environments like 802 11x Wi Fi Wi Max 3G cellular and satellite based Internet connections Those of us here who have been remote broadcasters have been wishing for a system like this for a long time As former broadcasters turned de signers it s our hope that this kind of enabling technology will tickle the imagination of the user enabling more creative and entertaining program ming to be broadcast from more diverse and interesting locations Please let us know about your unique ideas and adventures by dropping us a note at techies comrex com COMREX CORPORATION Asout BRIC BRIC Broadcast Reliable Internet Codec is a breakthrough technology with hardware that will deliver audio over the public Internet in much the same way that ISDN and POTS codecs have performed in the past BRIC consists of three pieces e Rackmount ACCESS codec which you are using es Portable ACCESS codec e Switchboard Traversal Server We will describe each piece independently 1 Rackmount ACCESS codec This product is designed for installa tion in a radio station s remote rack and is designed for always on operation Hence the lack of a power switch Also it is envisioned that this product will be controlled entirely from a computer connected to the local LAN There are no user controls on the ACCESS Rack oth
57. S COMREX CORPORATION AND ITS SUPPLI ERS DO NOT WARRANT THAT THE PRODUCT IS ERROR FREE THAT ALL ERRORS MAY BE DETECTED OR CORRECTED OR THAT THE USE OF THE PRODUCT WILL BE UNINTERRUPTED IN NO EVENT WILL COMREX CORPORATION AND ITS SUPPLIERS BE LIABLE FOR INDIRECT INCIDEN TAL SPECIAL OR CONSEQUENTIAL DAMAGE RESULTING FROM THE USE OF THE PRODUCT INCLUDING LOSS OF PROFITS LOSS OF SAV INGS LOSS OF USE OR INTERRUPTION OF BUSINESS EVEN IF COMREX CORPORATION OR ANY OF ITS SUPPLIERS HAS BEEN ADVISED OF THE POSSIBILITY OF SAME IN NO EVENT SHALL COMREX CORPORATION AND OR ITS SUPPLIERS TOTAL LIABILITY TO YOU REGARDLESS OF THE FORM OF ACTION EXCEED THE AMOUNT YOU PAID AS PART OF THE PURCHASE PRICE OF THIS PRODUCT COMREX CORPORATION AND ITS SUPPLIERS MAKE NO WARRANTY EITHER EXPRESSED OR IMPLIED THAT ANY USE OF THE PRODUCT WILL BE FREE FROM INFRINGEMENT OF PATENTS COPYRIGHTS OR ANY OTHER THIRD PARTY S INTELLECTUAL PROPERTY RIGHTS THE SOFTWARE OWNED BY COMREX CORPORATION OR BY ITS SUPPLI ERS RESIDING IN OR OTHERWISE ASSOCIATED WITH THIS PRODUCT ARE PROTECTED UNDER COPYRIGHT LAW AND INTERNATIONAL TREA TIES UNAUTHORIZED REVERSE ENGINEERING REPRODUCTION AND OR DISTRIBUTION OF THE PRODUCT OR ANY PORTION THEREOF IS STRICTLY PROHIBITED AND MAY RESULT IN CIVIL AND CRIMINAL SANC TIONS AND WILL BE PROSECUTED TO THE FULL EXTENT OF THE LAW COMREX CORPORATION AND ITS SUPPLIERS OWNS AND SHALL RETAIN ALL RIGHT TITLE AND INTEREST IN AND TO ANY SOFT
58. S AAC Option required Build a profile using the Profile Manager on either the ACCESS Rack or Portable and select a Channel Mode of Standard RTP Then choose a Luci compatible encoder for the outgoing call The Luci software will control what type of stream if any is returned to the ACCESS 113 COMREX CORPORATION 2 Zephyr Xstream Xstream Firmware version 3 2 0 and higher sup port an RTP Push function that is compatible with ACCESS in some modes ACCESS is not currently compatible with the Xstream s HTTP and SIP streaming functions There are several limitations imposed by the Xstream when using the RTP Push function On the Xstream only AAC and MP3 coding are available in this mode and ACCESS is only compatible with the AAC mode The Xstream uses downsampling in modes below 96Kb s which is not supported by ACCESS In order for an Xstream to decode an ACCESS stream the default decoder setting must be changed from lt Auto gt to lt AAC gt in the codec menu of the Xstream To communicate with a Zephyr Xstream a Initial Setup This will define all Standard RTP connections to be Xstream Compatible i ACCESS Rack On the System Settings Tab open the Stan dard RTP Settings option and choose RTP Compatibility Mode On the pull down box select Zephyr Xstream ii ACCESS Portable Choose Configure then System Settings on the display Under Standard RTP Settings select RTP Compat ibility Mode
59. T staff if you tried NAT routers need directions to correctly A forward unsolicited data Incoming Packet For 70 22 155 130 Where does this go Codec B 192 168 1 101 192 168 1 102 Figure 37 Incoming Packets Hitting NAT Router In describing NAT routing it s important to understand the concept of ports These are numbers like the source and destination IP addresses that are attached to each packet to further qualify which application on a computer or codec is meant to send or receive a packet In a typical codec application unit X will send a packet from address A port B to address C port D on the destination codec Y A codec that has multiple applications running like streaming audio while simultaneously serving a configuration web page would deliver these applications from and to different port numbers but perhaps to the same IP address Port numbers are also used by NAT routers in segmenting applications flowing through them and they may change source port numbers at will ACCESS Product Manual Network Address Translation NAT refers to the ability of a router to translate requests from computers or codecs within its LAN onto the public Internet On its most basic level this involves replacing the private source or return IP address in each packet with the true public IP and remembering where that packet was sent so that any response can be forwarded back to the proper device A goo
60. TION 1 INTRODUCTION Congratulations on purchasing the Comrex ACCESS codec This product is the next step in the evolution of audio transportation over networks For Comrex this began in 1976 with the introduction of the Frequency Extender followed by ISDN codecs in the early 1990s and POTS codecs in 1996 So we ve been doing this for a long time The ACCESS product is the result of years of our research into the state of IP networks and audio coding algorithms This has all been in the quest to do what we do best which is to leverage existing available services to the benefit of our core customers radio remote broadcasters The heart of this product is called BRIC Broadcast Reliable Internet Codec While others have introduced hardware coined IP Codecs this is the first product we re aware of that dares to use the word Internet with a capital I Given the challenges the public Internet presents it s no small boast to say that this product will perform over the majority of avail able connections BRIC represents a change that is both desirable and inevitable for remotes It s inevitable because as available connections move from old fashioned circuit switched style to newer packet switched style technology like ISDN and POTS codecs will begin to work less and less often The desir ability stems from the new wireless networks that will make remote broad casting more mobile simpler and less expensive B
61. TRIGGERED CONNECTIONS 118 A remote entry using a unidirectional profile can still utilize the tools required for automatic connection To set up a connection to be always active i e reconnect in the case of power outage or network failure choose that connection on the System Settings Tab as the Always Connect To location To trigger the connection when an external contact is closed choose the connection under one of the Contact Closure settings on the System Settings Tab ACCESS Product Manual APPENDIX D CONNECTIONS AUDIO SPECIFICATIONS POWER PHYSICAL SPECIFICATIONS Power IEC 530 Inlet Analog Line In Left Digital AES3 In Analog 3 pin XLR female pin 1 ground pin 2 pin 3 Digital 3 pin XLR female pin 1 ground pin 2 data pin 3 data AES 3 Output 3 pin XLR male pin 1 ground pin 2 data pin 3 data POTS PSTN 6 pin RJ 11 modular jack pin 3 tip pin 4 ring Contact Closures 9 pin D male pinout in Section 2 PS 2 Keyboard Mouse 6 pin mini DIN female for PS 2 Keyboard Mouse Serial w adapter 9 pin D female RS 232 pinout Monitor 15 pin D female VGA monitor pinout USB 2 USB Type A Ethernet 8 pin modular 1OOBASE T wiring Line Inputs Type Balanced Impedance 50k Ohms pins 2 3 Level 0 dBu nominal 20 dBu max Line Outputs Type Balanced Impedance 100 Ohms pins 2 3 Level 0 dBu nominal 20 dBu max Frequency Response Varies with algorithms
62. URES FOR COMREX ACCEaa e LOS E ACCESS Bric LInK TRAVERSAL SERVER USE DISCLAIMER e LOS EE CONFORMITY AND REGULATORY INFORMATION e LOO Eechen IP COMPATIBILITY EENG SE ege INFORMATION FOR IT MANAGERS e LIS GEN Usinc ACCESS ON UNIDIRECTIONAL NETWORKS e LIZ Ee EELER ege eege Eege 119HQ debbaadiaee Tabie EE LL seines TABIE 2 ABS3 EE LL ege deg TABLE 3 CONTACT CLOSURE Droe LD ee TABLE 4 SERIAL PORT PINOUTS JL Sieste FIGURE 1 REAR PANEL DIAGRAM AND DrsckipoOns e LO vets neuen FIGURE 2 FRONT PANEL DIAGRAM AND DESCRIPTIONS e LL s ngen FIGURE 3 DIRECT CONNECTION TO JwvpkwET e LE iiasteieee FIGURE 4 CONNECTION TO INTERNET VIA SUBNET OR LAN L4 ACCESS Product Manual Figure 6 TCP IP TAB FOR ETHERNET PORT CONFIGURATION 11 0 0eccceceeseseeceees 20 F Gure 7 POTS MODEM CONFIGURATION Zap 20 FIGURE 8 CONSOLE CONNECTION INTERFACE REMOTES Zap 21 FIGURE 9 ADD NEW REMOTE SCREEN vo scsscssecsscceccecescesceseeseeseseessuesaeseesens 22 FIGURE 10 CHANNEL STATS IN GRAPH FoORuar osese seeressrereessreens 24 FIGURE 11 CHANNEL STATS IN NUMERIC FORMAT 00cc0cceccsececeeeecssetsuesaeseesens 24 FIGURE 12 PEER STATS IN GRAPH FORMAT ou cccsccsccsecenecescneseseeescuseessustseseeeens 25 FIGURE 15 PEER STATS IN NUMERIC FORMAT 0 ccccc ccc ccececcsceccesuceesuscuseesusens 25 FIGURE 14 AUDIO METERING wicccccccccccceccesscesceusececsueseesssesesueesueesensseuseeaess 26 FIGURE 15 CONFIGURE TAB PULL DOWN Arenz
63. WARE SUPPLIED TO YOU IN AND AS PART OF THE PRODUCT AND ALL INTELLECTUAL PROPERTY RIGHTS RELATED THERETO THE SALE OF THE PRODUCT SHALL NOT BE CONSTRUED IN ANY MANNER AS TRANSFERRING ANY RIGHT OF OWNERSHIP IN ANY SUCH SOFTWARE 107 COMREX CORPORATION SEcTION 19 TRAVERSAL SERVER DISCLAIMER 108 ACCESS BRIC LINnK TRAVERSAL SERVER Use DISCLAIMER You have purchased a product from Comrex that uses the Switchboard TS Traversal Server to provide the ability to locate Comrex hardware via the Internet and to aid in the making of connections when certain types of NAT routers are involved in the link Switchboard TS consists of two distinct elements The firmware that functions within the codec hardware to enable use of the function and a server deployed on the Internet which provides the services to the codec hardware The purchase you have made entitles you only to the firmware elements within your codec that utilize these functions The functions of Switchboard TS as implemented in your codec are warranted to work as described according to standard Comrex warranty terms found in your User Manual when used with a properly functioning Traversal Server deployed on the Internet Comrex has deployed and provided you account details for a Switchboard TS account on our server located at http switchboard comrex com Comrex provides this service free of charge and at will As such Comrex offers no warranty as to availability of thi
64. abled ACCESS performs best when using UDP for connections but there are some rare circumstances when the system may need to be switched over to TCP operation This advanced option defines how incoming TCP calls are handled Outgoing calls are defined as TCP when their profile is configured ACCESS normally listens for incoming calls on both TCP and UDP ports and chooses the first to arrive If a TCP call is detected ACCESS will attempt to use the same TCP link to transmit in the reverse direction Accept Incoming Connections Allows you to turn TCP Auto Answer on and off Disabling this function means only outgoing TCP calls call be established IP Port You have the option of setting the incoming TCP port number which can be different than the UDP port number Note warnings given above about changing port numbers calls with mismatched port numbers will fail 53 COMREX CORPORATION SECTION 7 CREATING A REMOTE CONNECTION 54 Makinc Connections UsiNG THE WEB BASED INTERFACE The following section describes how to enter local remotes into the prod uct to dial them by IP address If you plan on using the Switchboard Tra versal Server or take only incoming calls this step may not be necessary For more on Switchboard Traversal Server see Section 10 So now it s time to make a connection on ACCESS We will assume that the proper network and audio connections have been made Before you can establish an
65. ajority of system settings relating to N ACIP SIP relate to Registered mode Registering with a SIP server in N ACIP SIP mode can have some advan tages When using a SIP server e The server can be used to help make connections between codecs through routers e The remote codec can be dialed by its SIP URI instead of IP address e The SIP server can be used to find codecs on dynamic IP addresses A SIP server exists in a domain This domain is represented by a web style URL like sipphone com or iptel org A SIP server or proxy generally handles IP connections within its domain The SIP server assigns a fixed alphanumeric name to each subscribed account For example an Iptel user may be assigned the user name comrex_user URIs consist of a SIP user name followed by a domain delineated with the symbol like an email address Our Iptel user s URI would be comrex_user iptel org Comrex devices do not use the designation sip before a SIP address If a connection is to be made exclusively within a domain the domain name can be left off As an example to make a call to this codec from another Iptel registered codec the dialing string can simply be comrex_user with the domain being assumed ACCESS Product Manual REGISTERING WITH A SERVER At a minimum you will need the following information when registering ACCESS with a SIP server 1 The Internet address of your SIP proxy server e g proxy01 sipphone com 2 The
66. and in order or half may arrive quickly with the other half delayed significantly In some cases most of the packets arrive in a timely manner but a small percentage of them may be extremely late In this case it s usually preferable to allow these late packets to be left out and keep the delay lower The decoder error concealment does a very good job of hiding these losses The Loss Cushion parameter instructs the buffer manager to ignore a certain percentage of late packets in its calculation The default value is 5 Applications that are not at all delay sensitive may wish to reduce this value to zero while extremely delay sensitive applications may prefer to have this closer to 25 Delay Cushion The jitter buffer manager usually works very hard to keep absolute delay to a minimum Some applications are not delay sensitive and would rather not have the manager working that hard The Delay Cushion setting is a way to instruct the manager not to attempt to drive the delay below a certain value E g if the delay cushion is set to 500mS this amount of fixed delay will be added to the buffer If the jitter manager needs to increase the buffer it will do so but will not fall below the 1 2 second level 47 COMREX CORPORATION SYSTEM SETTINGS TAB 48 Delay Limit The inverse of the Delay Cushion this parameter instructs the manager not to wind the buffer out beyond a certain delay value regardless of how many packets a
67. arked by other companies as AACPlus HE AAC and close derivatives are often used as the main audio codec for digital radio and satellite networks This algorithm further increases the efficiency of HE AAC by adding inten sity stereo coding This results in a lower bit rate for stereo signals We also cluster a very reduced rate HE AAC mono into this category although technically it does not contain v2 coding This algorithm is an extension of AAC developed by the FhG IIS who are the contributors to AAC and primary inventors of the MP3 algorithm It s quality is superior to MP3 at similar bitrates 64 128 kbps but it exhib its very low delay 100mS This choice is best when reasonable network throughput is assured near transparent audio is required and interactivity is needed This latest algorithm is a combination of the LD and HE AAC variants It provides the network conserving benefits of SBR along with the dramati cally reduced delay time of LD For low delay applications it s usually the best choice 81 COMREX CORPORATION SECTION 12 82 User A BRIC HQ1 Mono Mutti STREAMING Warning Advanced Topic ACCESS supports the ability to run one encoder per box But this single encoder stream may be sent to up to nine destinations simultaneously We call this capability multi streaming since the encoder creates a separate but identical outgoing stream to each decoder Note Your Internet connec tion mu
68. arrier If a good connection is found keep that line up ACCESS Product Manual Section 10 SWITCHBOARD TRAVERSAL SERVER TS The Switchboard Traversal Server is a service built and maintained by Comrex on the public Internet that provides users a directory of other users facilitating connections to devices that would normally have trouble accepting incoming IP connections Use of the Comrex Switchboard TS is free and comes activated from the factory The next section describes the theory of Switchboard TS If your primary interest is in enabling and using it skip to the section labeled Conricurinc Switchboard TS Switchboard TS is useful because it s not always the simplest thing to connect two devices which are essentially peers on the Internet and there are two major reasons why First of all to initiate a stream to a device on the Internet requires that you know its IP address This is the number that gets applied to the destination field of the IP packet so the Internet routers can figure out how best to send it along its way Every device that connects directly to the public Internet must have one but when web browsing or sending email this information is usually hidden from the user In the traditional client server scenario like web surfing a Uniform Resource Locator URL is used to represent the IP address of the web page which is decoded by a DNS server Once a computer requests a web page from a web server the web
69. ast receiver has no effect The important settings for Multicast are e Sender Receiver Determines whether this particular ACCESS is de signed to generate the IP Multicast stream send or decode one receive Encoder Type Determines the type of stream to be used by the Multi cast Encoder not relevant for decoders In addition to the basic options for IP Multicast profiles clicking the Ad vanced box will allow setting of the same Advanced Options available for Normal BRIC Unicast profiles See the Profiles Tab section for more information All Multicast connections are outgoing connections A Multicast Sender must initiate an outgoing stream and a Multicast Receiver must initiate an incoming one These remotes are configured within a special address range known as a Multicast Block typically 224 0 0 0 to 239 255 255 255 To establish a Multicast connection simply define a remote as having an address within the IP Multicast Block use an IP Multicast profile and press Connect Time to Live TTL is a variable set by Multicast encoders to determine how long a packet is processed before it is dropped by the network The default value of TTL in ACCESS is 0 which limits its use to within a LAN environment TTL may be manually changed on a Multicast Sender re mote by configuring the IP address followed by a followed by the TTL value An example remote Multicast encoder could be set for the address 224 0 2 4 25
70. at requests packet resends only when appropriate UDP reliability can be useful on some wireless connections that have unsatisfactory performance due to packet loss For POTS connections the choices are fewer Modem Mode POTS Codec is the default setting and emulates the coding channel of previous Comrex POTS codecs like the Matrix Vector and BlueBox products ACCESS does not support compatibility with Hotline codecs Stereo POTS allows connection between ACCESS users providing stereo audio over a dial up connection Compatible only with other ACCESS Connection Timeout Under normal circumstances a connection will be terminated on one end and the other end will drop the connection in turn But if a network failure occurs or a connection is ended abruptly e g killing power to an ACCESS the system will drop the connection after a pre determined time The default is 60 seconds but this can be shortened or lengthened here If an indefinite connection is required see Section 8 OPERATING ACCESS 1N A 24 7 Environment for additional information In order to use POTS Stereo Mode special configuration must be done on each end of the link Once an ACCESS is set for incoming POTS stereo connections normal mono POTS codec compatible calls can not be received until the settings are changed back Outgoing unit settings usually the field unit The outgoing ACCESS will dial the phone call but a profile for the outgoing call that specifi
71. ault settings WARNING All settings profiles remotes and other changes will be lost in this procedure This function is not reversible and should be used only as a last resort to restore factory settings 33 COMREX CORPORATION SECTION 6 ACCESS WEB BASED INTERFACE 34 Gaininc Access to ACCESS via THE WEB BASED INTERFACE Once your IP settings are configured and ACCESS has cleanly booted on your LAN it s time to take a look at the ACCESS Web based Interface This is done by pointing a web browser on your LAN to the ACCESS IP address To do this simply type the address into the URL bar of your browser You will need Internet Explorer 6 or higher or Mozilla Firefox 1 0 or higher with Adobe Flash player Opera 8 5 works well also If you experience trou ble connecting to ACCESS be sure to check that your Adobe Flash player is current Go to the following link to check and update your flash player http helpx adobe com flash player kb find version flash player html Once you are connected to ACCESS a login screen will appear see Figure 20 Key in any user name along with the default password comrex case sensitive to get to the Main User Interface display This display is opti mized for full screen mode F11 on most browsers on a 1024x768 display Figure 20 Web based Interface Login Screen ACCESS Product Manual There are three main parts to the ACCESS Web based Interface screen 1 Main Audio Meter T
72. ayed in its own list It does not have any impact on how that codec is displayed on other devices Comeex Ove Gow Audio Codecs 8 AN Neen ACCESS ack Mee AM Sean VA oo 28639 ACCESS Porte asemana EI ACCESS Sensex Koenig E D ACCES Retain temrmentont E socca wxc csan 186 88 Figure 46 Changing Active Contact List As shown in the Switchboard web interface you can select one of your individual codecs and change the Active Contact List from default This will change the list of codecs displayed on that unit In the case where you d like to allow users outside your account see the status of some devices in your fleet Switchboard has implemented Shares Shares are subsets of your codec fleet that you define Once defined you can invite other Switchboard accounts to add your Shares and your codecs become visible to them 77 COMREX CORPORATION 78 Shares are a one way transaction If you invite an external user to share and he accepts you don t get any additional status on your codecs The external users must create a share and invite you for the share to be two way Shares are created by clicking the top tab entry labeled Shares A list of your current Shares appears and you can added more by clicking Add New Share Share a Device lt Back to all Shares Share Information Share Name Little Radio stringers Units to Share City Hall ACCESS Rack 00 40 63 de 7a c Master Con
73. be used for some other reason Under Advanced System Settings a field is available called Public IP Override Any address put into that field will be pasted into the address SIP field So if you know what your public IP address is can be gotten from many websites via a browser you can manually paste it here Keep in mind this is often subject to change over time and obviously if you use a different network so it s important to remember this change has been made on your codec 95 COMREX CORPORATION SECTION 17 Questions amp ANSWERS 96 ADVANCED ToPics This section discusses some frequently asked questions and possible solutions encountered when setting up configuring troubleshooting and achieving optimum ACCESS performance Q How do I choose which encoding algorithm to use A ACCESS offers a very wide range of encoding algorithms To some this may seem daunting Here s a short guide and comparison chart on how to choose what s best for your application 1 Do I have lots and lots of bandwidth If you re running on an entirely unconstrained network like a campus LAN or local Wi Fi Mono or Stereo Linear Mode will offer the highest audio quality with lowest delay If you re hitting the public Internet at any point in the link however avoid Linear Mode 2 Do I require interactivity If you need to chat back and forth across the link choose one of our low delay algorithms like BRIC ULB BRIC HQ1 or AAC
74. cally uses POTS Stereo Mode must be built This is done by creating a new profile in the Profile Manager Select Channel under Global Settings and then Modem for the outgoing channel Under Local Settings choose a Modem Mode of Stereo POTS Once the profile with these parameters is built it can be named and assigned to any outgoing remote that uses a phone number rather than an IP address as its destination ACCESS Product Manual Additional profiles may be built utilizing the normal POTS codec modem mode if desired You can then build two remotes to the same phone number one using your stereo profile and one using your legacy compatible POTS codec profile Incoming unit settings usually the studio unit The incoming unit will receive the call from the field In this case the ACCESS must be configured to treat all incoming calls as POTS Stereo Mode This is done in the System Settings section by selecting Modem Mode under Modem Settings To receive stereo calls this setting must read Stereo POTS To receive calls from older Comrex POTS codecs or ACCESS configured to emulate them the setting must be POTS Codec 43 COMREX CORPORATION ADVANCED CHANNEL 44 Warning Advanced Topic ADVANCED PROFILE OPTIONS The options available in the default mode should provide good performance for most users but in some circumstances it may become important to fine tune some of the more obscure parameters that
75. cause they must choose addresses that are not in use by the Internet at large They will likely choose an address at one of 3 distinct ranges 192 168 x x 172 16 x x 10 x x x 15 COMREX CORPORATION 16 Also on 192 168 style and 172 16 style subnets the third entry will typi cally be a single digit often 0 or 1 You can usually find out the DHCP assignment style by querying a Windows computer on the same LAN using Run gt Cmd gt ipconfig If you know your DHCP server assigns addresses us ing one of the first two formats or you know the DHCP assignment range on a 10 x x x network you can usually derive the true IP address by the front panel LEDs They will display a coded version of the IP address as signed for a few seconds during boot just before the ACCESS enters opera tional mode During this time the Ready light on the front panel flashes quickly and the Level LEDs display the last 4 digits of the IP address This is best shown by example Assume you are using a Linksys router on your network that has a built in DHCP server You may be aware that by default this router assigns IP addresses using the range 192 168 1 2 255 Let s assume that when con nected the ACCESS is assigned an IP address of 192 168 1 7 The LEDs will display the last four decimals of this address including zeros so during boot you will see the following code L Send will display 1 LED R Send will display 0 LEDs L Receive will display 0
76. committee was formed by the European Broadcast Union called N ACIP to hammer out a common protocol to interconnect codec brands This committee resulted in the establishment of EBU3326 a technical document describing how best to achieve this goal EBU3326 by and large establishes a set of features each codec should sup port then leaves most of the heavy lifting to other previously established standards like SIP IETF RFC 3261 Topics not covered yet by EBU3326 include things like carrying ancillary data and contact closures from end to end codec remote control and monitoring and complex NAT traversal which at this point are still left to the individual manufacturer s discretion So if these topics are important to your application it s best to stick to a single codec vendor and their proprietary protocols The Tech 3326 document defines several mandatory encoding algorithms and the transport layer that could be used on them for compatibility But the most complex part of the standard was the decision on how to arrange Session Initialization which is the handshake that takes place at the start of an IP codec call The most commonly used protocol is called SIB which is used extensively by VoIP phones and therefore was a logical choice SIP carries the advantage of making ACCESS compatible with a range of other non broadcast products like VoIP hardware software and even mobile phone apps ACCESS does not fully comply with EBU3326
77. d and CORE SDI S A 105 COMREX CORPORATION WARRANTY 106 Further copyright notice for ncurses dropbear PuTTY and libxml2 Permission is hereby granted free of charge to any person obtaining a copy of this software and associated documentation files the Software to deal in the Software without restriction including without limitation the rights to use copy modify merge publish distribute sublicense and or sell copies of the Software and to permit persons to whom the Software is furnished to do so subject to the following conditions The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software Libpcap tcpdump Copyright 1988 1989 1991 1994 1995 1996 1997 The Regents of the University of California All rights reserved Redistribution and use in source and binary forms with or without modifi cation are permitted provided that the following conditions are met 1 Redistributions of source code must retain the above copyright notice this list of conditions and the following disclaimer 2 Redistributions in binary form must reproduce the above copyright no tice this list of conditions and the following disclaimer in the documenta tion and or other materials provided with the distribution 3 The names of the authors may not be used to endorse or promote prod ucts derived from this software without specific prior written permission
78. d metaphor for this would be that an outgoing packet punches a hole in the router through which authorized reply packets may be returned to the codec for a limited time as shown in Figure 38 Punching a hole in a NAT Router 2 Reverse channel stays open for response packets 1 Codec sends a packet out through router Figure 38 Punching a Hole in a NAT Router The Traversal Server aids in breaking through these different types of routers for incoming calls Because it is in constant contact with all subscribed codecs it can send and receive test patterns to determine whether one or more NAT routers exist on a link and what type they are It can then choose a connection method to be used to circumvent the problem Options available to it include e Instructing the calling codec to make a normal connection No NAT detected e Using the hole punched by connection to the Directory Server for incoming connections from other codecs e Instructing the called codec to make the connection in the reverse direction 71 COMREX CORPORATION CONFIGURING SWITCHBOARD TRAVERSAL SERVER 72 The second option which utilizes the outgoing Directory Server ping described earlier is very useful The interval of this ping is adjustable but defaults to about one minute which is short enough to keep a hole punched through the majority of NAT routers These techniques are based loosely with enhancements on a gener
79. d of your ACCESS link with a public IP In a radio remote environment this should probably be the studio end since you will often have much less control on the remote side ACCESS can be set to its own fixed IP address referred to as Static in Internet speak or can obtain its address from the network known as Dynamic or DHCP This concept is entirely independent from the Public vs Private concept Public and private addresses can each be dynamic or static Dynamic DHCP ACCESS is set by default to DHCP addressing mean ing that it looks to your network for assignment of an IP address If your network has a DHCP server and this is the way you intend to use it you don t need to alter any settings in the Console Connection Interface You will however need to know what address is being assigned to ACCESS by the network This is easily done by attaching a computer monitor to the VGA port on ACCESS before applying power After ACCESS boots it will display the current IP address on the monitor Note DHCP addresses can change over time so you may need to recheck the address if you are hav ing trouble connecting Finally there s one other way to determine the IP address of ACCESS If you re unable to put a computer monitor on the system you can infer the IP address by what s displayed on the front panel LEDs for a few seconds during the boot process DHCP servers typically assign IP address in a standard format This is be
80. ddress and has no idea what the public address is So naturally it will put its private e g 192 168 x x style address into that return address field The called codec will dutifully attempt to connect to that address and undoubtedly fail since that can t be reached from the Internet at large Incoming calls to codecs behind routers are complicated by the fact that ports on the router must be forwarded to the codec In the case of SIP this must be three discrete ports For Comrex codecs these are UDP 5060 5014 and 5015 lt 6014 and 6015 with 3 0 firmware gt And since even the for ward address is negotiated in SIP the incoming unit is likely to populate the forward address field with its private address as well ACCESS Product Manual SOLUTIONS STUNNING SUCCESS Fix oF Last RESORT Many times the return address field issue is fixed by the SIP server in Registered mode and no compensation measures are necessary Often in fact the server insists on acting as a proxy and handles all the traffic itself outgoing and incoming streams are relayed directly by the server solving any router issues But in point to point connections this isn t possible All is not lost here since we can find some hacks to make this work The first place to look is your router since many modern routers are aware of this issue and have taken steps to relieve the pain If your router supports a SIP Application Layer
81. ddress is 192 168 1 57 i Enable Configure Bottom j EL ss Menu Arrows Enter Navigation Figure 5 Top and Bottom Navigation Bars 18 ACCESS Product Manual NETWORK TAB NETWORK TAB ETHERNET Port SET UP The Network Tab is shown in Figure 5 The Ethernet port and POTS modem may be individually enabled and configured via this interface The main tab of interest in configuring the Ethernet port is shown in Figure 6 the TCP IP Tab Use the drop down menu to select one of the four configuration options for Ethernet Static DHCP PPPoE Gateway For DHCP Dynamic connections simply select DHCP and the unit will automatically obtain the network settings If your connection requires a static or fixed IP address you can enter that along with your subnet mask and gateway information in the appropriate fields If you know the address of your DNS server enter it here This is required for use of Switchboard TS and the internal browser functions PPoE Point to Point Protocol over Ethernet is used by some DSL and WiMAX services to establish and end sessions much like a dial up modem does Most IP connections don t use it and it can usually be ignored If your ISP requires PPoE session to be established rather than entering IP information you may enter a user name and password to establish connection These are supplied by your ISP PPoE connections always use dynamic IP addressing Wh
82. dec itself the user will input a familiar name by which the codec will be known within that group See the CONFIGURING SWITCHBOARD TRAVERSAL SERVER section for instructions on how to log in to the server ACCESS Product Manual Once enabled whenever a codec in the group gets physically connected to the Internet by any means 3G card satellite Ethernet etc the unit will sync with the server The current public IP address of the codec will be obtained by the server and the user directory will be updated with the new IP In addition the availability status of the codec is also updated The codec will ping the server if anything changes address status etc As we ll see this ping function will prove useful in other ways Once the codec has updated its status with the server it s time to download the directory This process happens instantly The update includes current addresses and status info for all codecs within the group As shown in Figure 36 this information forms a sort of Buddy List that gets integrated into the codec s connection address book The list may still consist of entries made manually by IP address into the codec but those are signified by a different icon Current status of each codec is reflected by graying out entries which are not currently connected or that haven t been synchronized to the server for any reason As shown in the diagram IP addresses are not displayed at the first level as
83. ders This will reduce overall bandwidth and enhance reliability on many networks You may also need to increase Delay Cushion on the non wireless decode side as described in the previous answer Q Dm paying for my network bandwidth by the megabyte How can I conserve A Set both Local and Remote encoders in the profile to BRIC ULB which uses by far the lowest amount of data While setting the profile click the Advanced Options and set both Local and Return Frames per Packet setting to 4 This will decrease overhead and preserve bandwidth Finally if you don t require audio in both directions disable the return channel by turning off the Remote Transmitter in the profile As a guide an ACCESS set this way will average about 8 minutes of talk time per mega byte in each direction Q How can I change modem parameters like dial tone detect and ring cadence detection A Contact Comrex for more info on this Q I notice in the Advanced Options that I can change my streaming from UDP to TCP Should I A Not if you want the best overall performance ACCESS is optimized in terms of data rate stability and delay to use UDP TCP mode increases overhead and delay and is included only for environments where UDP is hopelessly blocked by a firewall ACCESS decoders do listen to both TCP and UDP ports and choose whichever arrives first If an ACCESS gets an incoming TCP connection it will establish TCP in the other direction automatica
84. e connections over modem PPP This option will open a graphical web browser and allow you to test your Internet connection by looking at a web page This browser does not support Flash and other complex protocols but is suitable for basic Internet use The browser is also helpful in scenarios where the local LAN requires that users log in via a web based security page as in many hotels The browser does not have a close button but the socket it creates will close automatically when an audio connection is made The Remotes Tab shown in Figure 8 is the first screen to appear when the system is turned on It allows you to define and edit your outgoing connections as well as indicate the presence of incoming connections Network Remotes Stats Configure Select Remote ACCESS Unit RB Loopback H B Comrex Lab Voice Comrex Lab Music ie Sddress 70 22 155 132 9000 Profile HOL Default e Gi Q Fl Menu Arrows Enter Navigation amp Ss Figure 8 Console Connection Interface Remotes Tab 21 COMREX CORPORATION 22 This section describes how to enter local remotes into the product to dial them by IP address If you plan on using the Switchboard Traversal Server or take only incoming calls this step may not be necessary For more information on Switchboard Traversal Server see Section 10 By default three remotes are already present on the Remotes Tab and can be used immediately for
85. e uses the Free Lossless Audio Codec algorithm for stereo send and receive audio FLAC can conserve network bandwidth by 30 40 with no loss of audio quality and only slightly higher delay when compared to Linear PCM FLAC still requires a much higher network bandwidth than is available on most public Internet links There are several additional factory profiles that use the industry standard AAC Audio Encoders including AAC AAC LD HE AAC amp AAC ELD 29 COMREX CORPORATION PROFILE SETTINGS 30 ACCESS provides a powerful set of controls to determine how it connects The Profiles Tab allows you to define one or more profiles to assign to outgoing remote connections It s often not necessary to define any pro files since ACCESS ships with a set of default profiles that cover most users But this tab allows you to build custom profiles to allow for differ ent encoders in each direction special POTS coding modes and special options for jitter buffer management Keep in mind that these profiles are useful only for connections initiated from the local ACCESS Incoming con nections are defined by the ACCESS at the other end Profile creation is segmented into commonly used and advanced options In order to simplify the interface Advanced Options are normally hidden from the user Remember building a profile doesn t change how any remotes are con nected until that profile is assigned to a remote on the Connections Tab
86. ective 89 336 EEC EN 55022 1998 A1 2000 Class A Conducted and Radiated Emissions EN55024 1998 A1 2001 A2 2003 Immunity ITE Equipment Low Voltage Directive 72 23 EEC EN 60950 1 2001 Information regarding configuration of this equipment for operation on the telephone networks of the EC countries may be found in the Comrex ACCESS Rack product manual Contact person Thomas O Hartnett V R Engineering Signed ft Aen Date 23 January 2006 ACCESS Product Manual U S AND CANADIAN REGULATORY INFORMATION FOR THE ACCESS RACK This equipment complies with Part 68 of the FCC rules and the require ments adopted by the ACTA as well as the applicable Industry Canada technical specifications On the bottom of this equipment is a label that contains among other information a product identifier in the format US DXDMDO1BACCRK If requested this number must be provided to a U S telephone company Telephone line connections to the Comrex ACCESS Rack are made via an RJ11C jack A plug and jack used to connect this equipment to the prem ises wiring and telephone network must comply with the applicable FCC Part 68 rules and requirements adopted by the ACTA A compliant tele phone cord and modular plug is provided with this product It is designed to be connected to a compatible modular jack that is also compliant See installation instructions for details The REN is used to determine the number of devices that may be con nected to
87. ed by a fax machine usually provides this direct access Be sure to disconnect the fax machine before connecting the codec 2 Check to see that there are no extensions or modems on the line you are using or at least arrange that no one uses these during your broadcast 4 If there is call waiting on your line disable it by entering 70 in front of the number you are dialing 5 If possible try the POTS codec out at the remote site before your actual broadcast at about the same time of day that you plan to use it This will give you a good idea of expected connect rates and possible line problems 6 At minimum connect a few minutes before airtime to assess the connec tion quality Setting a MaxRate on the POTS codec based on your findings is highly recommended MaxRate usually should be set at a level or two below the maximum unrestricted rate This will provide a guard band of sorts against noise and corruption which may cause errors on the line 7 If operation starts to degrade after a long period of connection it may be that the phone line parameters have changed These parameters are affected by factors such as time of day weather and geographic location The modems should be given the opportunity to renegotiate for these new parameters 8 If you experience low connection rates or errors try redialing If that does not help dial from the other end If the call is long distance try forcing the call to another c
88. efault static IP ad dress network mask and DHCP pool information Since this is usually Ethernet this is done in the normal Ethernet TCP IP Tab Simply select Gateway in the pull down menu as shown in Figure 52 In Gateway Mode ACCESS is acting as a DHCP server and router to the other devices It will assign a dynamic address to all devices connected to it on the LAN The static address assigned to the ACCESS Ethernet port is 192 168 42 1 The pool of addresses assigned by the DHCP server is 192 168 42 128 192 168 42 192 Network Remotes Stats Configure Configure Network Device General TCP IP Gateway lz IP Address 192 168 42 1 Network Mask 255 255 255 0 A DHCP server will run on this network device allowing you to use the ACCESS unit as an internet gateway for devices such as laptop PCs Cancel Save Q Fl Menu Arrows Enter Navigation Figure 52 TCP IP Tab for Gateway Setup ACCESS Product Manual SeEcTION 16 Mors asout EBU3326 EBU3326 in ACCESS Make N ACIP SIP CompatiBLE CONNECTIONS Comrex codecs and many other brands have a set of protocols that allow easy IP connections between units In general when connecting between Comrex hardware it s best to use these proprietary modes to take the most advantage of the features of the product However many users are concerned about getting locked in to a certain codec brand Because of this an international
89. en using PPoE an IP address will be assigned by the DHCP server at the ISP and will appear on the bottom bar of the network menu The Gateway option is an advanced topic and is described in the Gateway OPERATION section It should not be enabled for most applications After the Ethernet parameters are set you may enable the Ethernet port For DHCP connections this will prompt ACCESS to acquire an IP address from the DHCP server Enabling and disabling the Ethernet port is equivalent to releasing and renewing IP addresses The acquired IP address will appear on the bottom bar of this display 19 COMREX CORPORATION Network Remotes Stats Configure Network Remotes Stats Configure Configure Network Device Configure Network Device General V TCP IP E Static Address tically in DHCP mode PPPoE Gateway C PPP enabled Leave disabled for Matrix Vector compatibility Fl Menu Arrows Enter Navigation kal Fl Menu Arrows Enter Navigation o Figure 6 TCP IP Tab for Ethernet Port Configuration Figure 7 POTS Modem Configuration Tabs Network Tas POTS The modem in the ACCESS can be configured for either Non PPP Mode or MODEM SET UP PPP Mode as shown in Figure 7 Most users may leave the default settings Non PPP POTS Codec Mode is the default setting This is used to place a call to another codec directly over the telephone line with no
90. er than a recessed reset button and the only indications are audio meters and a Ready light to indicate an incoming data stream After initial con figuration all connection status and diagnostics are available via the internal web server and Console Connection Interface 2 Portable ACCESS codec This product is engineered to provide the most convenience for the remote broadcaster on the road It combines small size battery power clip on mixer and headphone drivers with an audio codec capable of remarkable quality on the public Internet 3 Switchboard Traversal Server This server exists on the public Internet at a fixed address and performs several functions Its use is op tional but makes connections between ACCESS codecs much simpler and removes worries about dynamic IP s NATs and other concerns that can make peer to peer connection over the Internet difficult especially over tightly controlled networks like 3G or Wi Fi The Switchboard TS provides the following functions a Communicates with all ACCESS codecs that are provisioned to work with it It keeps a log of the IP address of every codec that wishes to be subscribed b Maintains a keep alive channel to each codec subscribed allowing Traversal of firewall and Network Address Translators when receiving an incoming call c Provides each subscribed ACCESS codec with a Buddy List of other users their current status and will facilitate connec tion to
91. er to detect these events and avoid having the buffer manager react The squelch has several user adjustable parameters with good default settings These should normally be left where they are but there may be unusual circumstances where they should be changed ACCESS Product Manual Retransmit Squelch Trigger Determines the amount of time the decoder must experience 100 packet loss before the Retransmit Squelch function is triggered Default is one second Retransmit Squelch Max The longest period of data loss during which the squelch function is active the default is two seconds During the squelch period the buffer manager ignored the relative jitter experienced and does not adjust buffer size to compensate Jitter Window This parameter defines the amount of time in minutes that historical network performance is analyzed in order to make the rest of the calculations As an example if the Jitter Window is set to the default of five minutes and if a dramatic network event happens and the buffer manager reacts perhaps by increasing the buffer the event will be included in the manager s calculations for the next five minutes If the network experiences improved performance over this period the manager may choose to wind the buffer back down after the five minutes has passed Loss Cushion Packets may arrive at the decoder displaying a range of statistical properties They may arrive in reasonably good timing
92. es a 20mS audio frame with an over all encode decode time of around 60mS This makes BRIC HQ1 a good choice for real time interactive applications Low Digital Bandwidth BRIC HQ has a data rate of around 24 or 28 kbps for mono and 56 kbps for dual mono allowing it to travel over medium to low speed networks e Voice Music Capable BRIC HQ is designed as a voice codec but does a respectable job at encoding music e Dual Mono Mode Supports the encoding of two independent audio channels such as a dual language broadcast These two chan nels will be multiplexed into a single outgoing stream e Stereo Mode This mode uses matrixing to deliver stereo au dio at less than double the bandwidth BRIC HQ2 This encoder decoder provides high fidelity 12 or 15 kHz mono or stereo HicH Quarry 2 transmission at low data rates and reasonable delay Here are some details of BRIC HO2 e Medium Delay BRIC HQ2 uses a 64 or 80mS audio frame with an overall encode decode time around 260mS Interactive applications are possible using BRIC HQ2 in the forward direction and BRIC ULB or BRIC HQ1 in the reverse Low Digital Bandwidth BRIC HQ2 encodes at 24 kbps fora full bandwidth mono signal Stereo signals occupy 30 kbps Dual mono is not supported in BRIC HQ2 e Voice Music Agnostic BRIC HQ2 utilizes a blend of different audio coding techniques so it does a good job of encoding non voice audio e Mono Stereo BRIC
93. g calls is to assign different incoming ports to each device To transfer audio ACCESS uses a default source and destination port of 9000 If this is changed both the outgoing and incoming ACCESS must be made aware of the change 57 COMREX CORPORATION 58 Changing the port for incoming connections is done on the System Set tings Tab Because this can really mess things up if not done properly the function is hidden in the Advanced Options of this tab as shown in Figure 30 Access the Advanced Options by clicking the Show Advanced Options box in the lower left corner of the System Settings Tab GD Gm KE ACCESS GID Gap FW 2 8 p13 test4 FLASH GUI 2 84 Connections Statistics Audio Metering Profiles System Settings SYSTEM SETTING SETTING ADJUSTMENT EI a System Settings IP Port ADVANCED OPTION a Tracia Server Incoming network port El Contact Closures Aux Serial Settings E Security Settings Y BRIC Normal Settings CURRENT A g n DEFAULT 9000 Accept incoming connections E IP Port gt C HTP Settings 9000 undefined gt Modem Settings gt Standard RTP Settings gt N ACIP SIP Settings gt TCP Settings Show advanced options LS x Apply Setto Default Software Licensing CHAT Figure 30 Changing the UDP Port for Incoming Connections To change the destination port of an outgoing call you must add the port number to the IP address in the following format IP_address port_num
94. g the PS 2 style keyboard or mouse remove and re apply power after connection As shown in Figure 5 all menus on the Console Connection Interface contain the top and bottom navigation bars which contain shortcuts to various setup and status displays The top bar contains four tabs e Network Enable and disable the Ethernet Port or POTS Modem Configure IP parameters e Remotes Create and configure the addresses and profiles of the various Outgoing connections Essentially this creates an editable phone book of places you connect to eStats View network performance data of active connections e Configure Create profiles for outgoing connections manage how incoming connections are treated and change configurations of additional features like audio switching contact closures and incoming password security 17 COMREX CORPORATION The bottom bar contains the following shortcuts e Pickboard Allows use of the pop up keyboard for text entry and eliminates the use of a PS 2 or USB style keyboard s Chart Jumps immediately to the chat screen pickboard allowing text messaging to other ACCESS users F1 Arrow Enter As shown in the legend on the bottom of the page the F1 key on the keyboard provides access to the pull down menus and the Arrow and Enter keys are used to navigate Top Network Remotes Stats Configure Choose Network gt Ethernet Port mm POTS Modem Current a
95. he option the system will display the destination IP address and the profile for that remote Remotes will remain in this list until they are deleted or the configuration of the entire system is reset Existing remotes may be edited by highlighting one and selecting Remotes and then Change Remote Settings Incoming connections are displayed by their IP address or if also configured as outgoing connections by their names Incoming POTS connections are displayed as incoming To make a connection be sure your network is configured and enabled in the Network Tab Then from the Remotes Tab simply select an outgoing connection and choose Connect Choose Disconnect to end a connection 23 COMREX CORPORATION STATS TAB ACCESS provides lots of information on the Stats Tab about network performance This information is divided into Channel Stats which provides information about all incoming and outgoing data and Peer Stats which gives detailed information regarding the decoder buffer manager s functions Both sets of information are available on a text tree basis as well as graphical real time charts showing historical performance As shown in Figure 10 the Channel Stats provide real time graphs of outgoing and incoming packets Each column represents one second of outgoing data segmented into audio coding data blue and overhead like IP UDP headers RTP headers etc light blue The Numeric Channel Stats tab Figure 11
96. he Encoder Frames per Packet Allows the encoder to wait for X number of frames to exist before sending a packet This option differs from FEC because each frame is only sent once Setting this value to a number higher than one can reduce network usage at the expense of delay This is because packet overhead bits like IP and UDP headers are sent less often Log Statistics This function is used in factory diagnostics and should be left disabled unless instructed by Comrex support UDP Reliability Max Retransmissions This parameter allows you to set an upper limit on how much additional bandwidth is utilized by the BRUTE UDP reliability layer The default setting is 100 which allows the error 45 COMREX CORPORATION ADVANCED DECODER OPTIONS 46 correction layer to use the same amount of bandwidth as the audio stream As an example if your audio stream is consuming 80 kb s of network bandwidth and UDP Max Retransmissions is set at 50 up to 40kb s additional network bandwidth may be used for error correction Nagle Algorithm Nagle is applicable to TCP transmission only When Nagle is enabled encoder packets are sometimes buffered and concatenated into larger packets depending on the network It can be used to lower overhead on TCP networks but adding delay Advanced Decoder options have to do with how the jitter buffer manager performs This is the algorithm that determines based on network performance ho
97. he Internet at large Incoming Call Issues Incoming calls to codecs behind routers are complicated by the fact that ports on the router must be forwarded to the codec In the case of SIP this must be three discrete ports For Comrex codecs these are UDP 5060 5014 and 5015 lt 6014 and 6015 with 3 0 firmware gt And since even the forward address is negotiated in SIP the incoming unit is likely to popu late the forward address field with it private address as well So to clarify because SIP has this requirement it makes things more dif ficult and complex when connecting from or to behind a router than the default Comrex connection mode Work Arounds All is not lost here since we can find some hacks to make this work The first place to look is your router since many modern routers are aware of 103 COMREX CORPORATION 104 this issue and have taken steps to relieve the pain If your router supports a SIP Application Layer Gateway ALG then enabling this option can fix the issue Essentially the router will get smart enough to read your SIP hand shake find the outgoing address field and replace it with your public IP This is a pretty slick solution but there may be environments when you are not aware whether this option is supported on your router or have the ability to enable it So on to solution two STUNning Success Another technique for working around the SIP Router issue is by using a protocol called
98. he level meters are defaulted to off to conserve bandwidth and client CPU but when these are enabled this top bar emulates the front panel of ACCESS 2 Tabs Use these tabs to control and obtain status of ACCESS They are described in detail in the next four sections 3 Chat Window Allows for a chat utility between any users that are logged into that particular ACCESS web interface In addition when ACCESS is connected to a remote user chat text will appear from any users logged into the remote web interface 4 Registration Status This window provides various network information and status including Traversel Server status if licensed SIP registration status the units public IP address and NAT type 1 COD COND e ACCESS EID CNTD FW 2 8 p10 FLASH GUI 2 7 1e Genee Sates 1 avao morerna sytem Seng REMOTE ACCESS UNITS Name Loopback CHAT Comes Lab Voice 70 22 155 131 not connected e Comrex Lab Music 70 22 155 132 not connected Leem Address Current State Receive Status Profile Last State Transmit Status e 127 0 0 1 not connected lade REGISTRATION STATUS TRAVERSAL SERVER STATUS DISABLED SIP STATUS ONLINE 200 OK PUBLIC IP ADDRESS 70 22 155 131 NAT TYPE Open _ SY a kabel Remove Stored Remote Change Remote Settings Send Figure 21 Web based Interface Screen 35 COMREX CORPORATION CONNECTIONS TAB 36 The
99. ic Internet protocol called STUN Simple Traversal of UDP through NAT The system works well in all environments except one when both users are sitting behind a symmetric NAT In this situation calls will fail even with Traversal Server The only option in that environment is to resort to port forwarding on one side of the link Switchboard TS is licensed to your codec when delivered from the factory An account on the Switchboard TS is required and can be obtained by contacting Comrex at 978 784 1776 or 800 237 1776 or by emailing techies comrex com or info comrex com Settings can only be changed via the Console Connection Interface The Traversal Server setup page is found in the Traversal Server section of the System Settings menu as shown in Figure 39 Network Remotes Stats Configure System Settings amp Auxiliary Serial Di Connections Contact Closures DL Security Traversal Server TS Enabled Enabled TS Address ts comrex com i TS Port 8082 Show Offline Units Not Enabled BRIC Normal Settings amp Modem Settings E N ACIP SIP Settings D Standard RTP Settings TCP Sett ngs Gi Q Fl Menu Arrows Enter Navigation amp sees Figure 39 Traversal Server Settings ACCESS Product Manual LOGGING IN AND SETTING UP THE SWITCHBOARD TRAVERSAL SERVER The TS Enabled setting enables the Switchboard TS function on this codec If this option is disabled the codec w
100. ical ACCESS as the primary IP This is because ACCESS receiv ing incoming POTS calls cannot restore IP connections ACCESS Product Manual SEcTION 8 OPERATING ACCESS wa 24 7 ENVIRONMENT ACCESS can be easily set up for always on operation It will be helpful to describe a little bit about the ACCESS data transfer protocol before describing how to set the system up In BRIC Normal mode the default mode of operation ACCESS transfers all its audio data via the UDP protocol This is in contrast to most web based connections like browsing and e mail which use the TCP protocol UDP unlike TCB is not connection oriented i e no virtual connection actually exists in this protocol layer between the devices In UDP the transmitter simply launches packets into the network with the correct address hoping the network will make its best effort to deliver the packets in a timely fashion If a packet is delayed or lost no error message is sent and no packets are retransmitted It is up to the receiver to cover up any lost data if it can This allows the Internet to deliver packets with the smallest amount of overhead and delay Since there is no intelligent connection built between the codecs there isn t actually any connection to break in the event of network failure The encoder simply launches packets into the network regardless of whether they arrive or not If the network fails and is later restored the packets stream will be res
101. ifferent than the server proxy address then this field is used In a nutshell SIP establishes a communication channel from the calling device to the called device or server on port 5060 All handshaking takes place over this channel and a separate pair of channels is opened between the devices one to handle the audio and the other to handle call control The original communication channel is terminated once the handshaking is complete Note that firewalls must have all three ports open to allow calls to be established correctly Also port forwarding may be required to accept calls if your codec is behind a router The main area where SIP complicates matters is in how an audio channel gets established once the handshake channel is defined In the common sense world the call would be initiated to the destination IP address then the called codec would extract the source IP address from the incoming data and return a channel to that address In fact that s how the default mode of Comrex codecs work and it works well But SIP includes a separate forward address or return address field and requires that a codec negotiating a call send to that address only This is important in the case of having an intermediate server And this works fine as long as each codec knows what its public IP address is A unit making an outgoing call must populate the return address field But any codec sitting behind a router has a private IP a
102. ilizes a POTS optimized version of the HQ2 algorithm This mode utilizes intensity stereo coding so channels may not be used to send uncorrelated audio material i e they must be left and right channels of a stereo feed Again ACCESS does not have the ability to adapt between the two types of POTS calls it supports The proper mode must be selected before an incoming call of that type is received Accept Incoming Connections POTS calls must be answered automatically on ACCESS If this option is disabled no POTS calls will be answered and only outgoing POTS connections can be made For information on the N ACIP SIP Settings please see Secrion 16 MAKING N ACIP SIP COMPATIBLE CONNECTIONS 51 COMREX CORPORATION BRIC NORMAL SETTINGS MODEM SETTINGS STANDARD RTP SETTINGS N ACIP SIP SETTINGS 52 Warning Advanced Topic ADVANCED SYSTEM SETTINGS When the Advanced System Settings box is checked a few additional options are enabled IP Port This option allows you to define the incoming UDP port the number to be used for incoming IP connections The default is 9000 Note that since most ACCESS codecs attempt a connection on this port number changing it can mean ACCESS in the field must dial specifically to your new port number in order to connect An outgoing call must be made to a specific port number in the form of IP_ADDRESS PORT e g dialing port 5004 on the Comrex test line is formatted 70 22 155 131 50
103. ill no longer use the server The TS Address setting allows you to enter the address of the Traversal Server which defaults to ts comrex com This is unlikely to change but if you intend to set up a private server you ll need to enter the address of your server here The TS Port setting allows you to enter the TCP port of the Traversal Server which defaults to 8082 If you are using a private server you may need to change the port for your server here Show Offline Units is the final setting which determines how other codecs in your group are displayed If this is enabled all codecs in the group will always appear on the Remotes list including units that can t be located being greyed out If disabled non locatable units will not appear If you wish to change the name of your ACCESS unit as it appears to other Traversal Server peers you can set it via the Unit Name option of Connections in the System Settings menu In order to use Switchboard TS you must first have an account with the server A user name and password will be provided by Comrex You can log in to switchboard comrex com using that information Once you ve logged in we advise clicking Account Info and adding the information about the owner of the account You may also change the account password in this section The first time you log in to Switchboard TS you will see a notice stating that no units have been added to the account yet By clicking on Add New Unit y
104. l Settings HTTP Settings Modem Settings Standard RTP Settings N AICP SIP Settings and TCP Settings As with the Profile Tab basic options are shown by default Less used options are hidden until the Show Advanced Options box is clicked All of these settings are explained in detail under the Web based Interface SysTEM SETTINGS section of the manual Network Remotes Stats Configure System Settings Connections Unit Name 00 40 63 f2 71 fc Incoming Connection Password f Always Connect To None POTS Modem Tones Enabled Contact Closures CC Connect Status Not Enabled Connect on CC1 None Connect on CC2 None Connect on CC3 None L Connect on CC4 None E Security Remote Control Password comrex Remote Control Enabled BRIC Normal Settings Accept incoming connections Enabled EL Modem Settings Modem Mode POTS codec Accept incoming connections Enabled N ACIP SIP Settings Show Advanced Settings Fl Menu Arrows Enter Navigation Figure 18 System Settings Tab 31 COMREX CORPORATION USER INTERFACE 32 The User Interface Tab is shown below in Figure 19 The F2 keyboard key can be user assigned to any of the most commonly used ACCESS functions If you find you commonly use a function and are often scrolling through multiple menus to get there simply assign the F2 Key Behavior to the proper function to create a shortcut The Web Browser Home
105. large span the relative jitter is high If the light blue section of the graph is small or invisible over a time period there has been very little jitter present Based on the historical value of this jitter figure the buffer manager will expand or contract the receive buffer lengthening and shortening overall delay The time interval over which this measurement is assessed is called the jitter window and is adjustable in the Advanced Profile editor The work of the Jitter Buffer Manager is shown by the green line which is the target buffer delay that the system is trying to achieve based on measurements done over the jitter window The lower half of the Peer Stats display shows a real time and historical representation of frame loss If the decoder does not receive packets in time the chart will show a red line indicating percentage of lost packets over the one second interval The Numeric Peer Tab Figure 13 gives an indication of the same values instantaneously as well as call duration and other parameters Network Remotes Stats Configure Network Remotes Stats Configure Numeric Peer Stats Ul Nu ne ric J Graph Peer Stats 134 3n Call Duration 0 05 41 Transmit Delay 45 0 ms Receive Delay 142 0 ms Frame Loss Rate 0 0 Remote Loss Rate 0 0 Receive Rate 29 6 kbps Receive Overhead 16 0 kbps Transmit Rate 29 6 kbps Transmit Overhead 16 0 kbps Comrex Lab
106. lly One other note for use with TCP most of the information presented on the Statistics Tab is generated by the UDP functionality so you won t see much here using TCP ACCESS Product Manual EBU3326 SIP STUN AND IP COMPATIBILITY Q My IT guy has apparently had way too much coffee because his face is all red and he s running around yelling something about Sarbanes Oxley and crashing the corporate network Is there some thing I can give him to make him feel better about the security of the network and his life in general A Why yes We ve created a special document called Information for IT Managers which was written specifically to help keep the blood pressure and stress levels of IT managers within normal tolerance It can be found in the Appenpix B of this manual or in the Support section of our website at www comrex com Everything you always wanted to know about EBU3326 SIP STUN and compatibility with IP codecs but were afraid to ask by the Codec Answer Guy This paper describes everything you need to know about making ACCESS and BRIC Link codecs work with other vendors We re diving into some deep tech here so grab that last cup of coffee in the pot and hang the Do Not Disturb sign the office door We re going to take a leap here and as sume familiarity with concepts like public and private IP addresses NAT routers and application specific port numbers used by IP data If this isn t the case a good o
107. m and Descriptions Rack DIAGRAMS AND INSTALLATION wesch D wesch uo O E LINEIN LEFT AES3 IN p p 10 lt LINE o1 Cu 3 amp 4 1 AC Input 2 Analog AES3 Input Switch 3 AND 4 ANALOG AUDIO INPUT 5 AND 6 ANALOG AUDIO OUTPUT 7 AES3 Dicitat AUDIO OUTPUT S SERIAL PORT 9 MONITOR OUTPUT 10 RESET 11 POTS PSTN 12 CONTACT CLOSURES 13 PS 2 Mouse KEYBOARD PORT 14 ETHERNET PORT 15 USB Ports 10 yl dt This is an IEC connector for the main power ACCESS works on worldwide AC power at 110 240VAC 50 G60Hz auto detecting This switch determines whether the Line In Left AES3 In XLR connector is used for analog or AES3 digital audio input Apply balanced analog audio to be sent over the network here Left chan nel is used for mono encoding modes Level is set to OdBu 0 775VRMS nominal Full scale input is 20dBu Balanced analog audio is available at these ports Level is set to OdBu 0 775VRMS Full scale output is 20dBu A 48KHz AES3 stereo signal is available here AES3 output is available si multaneously with analog When the AES3 Input is active the AES3 Output will lock to the sampling rate and clock signal of the Input Asynchronous ancillary data is available here Attach a VGA computer monitor here for accessing the Console Connec tion Interface This button will
108. m is occurring in one direction or both If in only one direction take a look at network usage patterns on the local end of each ACCESS If someone else on your LAN is downloading large files on the decoder side or uploading large files on the encoder side this may cause some performance issues You may need to ask them to temporarily cease activ ity or investigate a network router solution that will offer ACCESS priority over other traffic Next take a look at the Status Tab on the ACCESS that is decoding the faulty audio Take a look at the jitter figure for your incom ing connection If this number is varying dramatically good networks keep this figure below 50mS then you may need to increase the Local Delay Cushion setting within the profile used to connect to that remote Although it will increase your audio time delay you may find increasing the cushion by 100 300mS or more will result in more stable connections since the jitter buffer manager will no longer attempt to reduce delay by making the buffer smaller than the cushion 99 COMREX CORPORATION 100 Q How can I optimize settings for EVDO UMTS or other wireless access A Since there is typically already a substantial delay in these networks it s often not a priority to keep ACCESS delay to the absolute minimum Using the profile that you set up for the EVDO connection enter the Advanced Options Raise the Frames Packet setting to 4 in both Local and Remote Enco
109. mation is correctly entered a new field appears in the Reg istration Status box located on the Connections Tab see fig 54 91 COMREX CORPORATION Makinc SIP REGISTERED CALLS 92 The status will reflect the progress of the registration process When com plete this will display Online If the box does not display Online after a short time it means that registration likely failed It s best to go back and carefully check the registration info It might also be useful to be sure the registration information is valid by configuring a VoIP phone or softphone with it and see if that registers SIP registration can be very simple with some servers and others can re quire more advanced settings There are several advanced settings available for use with SIP and they are described in the Apvancep Toric sections When registered calls made using a N ACIP SIP profile behave differently than normal The address field regardless of whether it is a SIP URI or an IP address is forwarded to the server No connection attempt is made until the server responds If the server accepts the address the call will be attempted If not an error message will appear in the status line Reasons for call rejection by a server are many Some examples 1 The server does not support direct connection to IP addresses if the address is in this format 2 The server does not recognize the address 3 The server does not forward calls beyond its ow
110. may be bandwidth firewall and security concerns with install ing ACCESS on a managed LAN it is recommended that your IT manager be consulted in these environments The details that follow assume a work ing knowledge of IT topics and network configuration We recommend putting ACCESS on a LAN and scoping out its functions before use To do this ACCESS must be given an IP address This is the In ternet location where you can connect to ACCESS through a web browser It will also be the address used when another ACCESS is connecting to it Every device on an IP network must have a unique IP address This is a number between 0 and 4 294 967 295 which is the range of values that can be represented by 32 binary bits For simplicity we break this 32 bit value into four eight bit values and represent each as a decimal number between 0 255 separated by dots For example the Comrex test IP num ber is 70 22 155 131 A device with a public Internet connection can either have a public IP ad dress which is directly accessible by the Internet or a private IP address which is directly accessible only by the LAN on which it is connected 13 COMREX CORPORATION Figure 3 shows connection of an ACCESS directly to the Internet using a public IP address Figure 4 shows connection to a subnet or LAN using a private IP address with a gateway router separating the LAN from the public Internet ACCESS Rack with public IP address of 70 22 155
111. mrex by phone at 978 784 1776 Our toll free number in North America is 800 237 1776 Product information along with engineering notes and user reports are available on our website at www comrex com Our email address is info comrex com Warranty and Disclaimer All equipment manufactured by Comrex Corporation is warranted by Comrex against defects in material and workmanship for one year from the date of original purchase as verified by the return of the Warranty Registration Card During the warranty period we will repair or at our option replace at no charge a product that proves to be defective provided you obtain return authorization from Comrex and return the product shipping prepaid to Comrex Corporation 19 Pine Road Devens MA 01434 USA For return authorization contact Comrex at 978 784 1776 or fax 978 784 1717 This Warranty does not apply if the product has been damaged by accident or misuse or as the result of service or modification performed by anyone other than Comrex Corporation With the exception of the warranties set forth above Comrex Corporation makes no other warranties expressed or implied or statutory including but not limited to warranties of merchantability and fitness for a particular purpose which are hereby expressly disclaimed In no event shall Comrex Corporation have any liability for indirect consequential or punitive damages resulting from the use of this product ACCESS Product Manual SEC
112. ms used by standard digital POTS calls and provide about 3KHz telephone quality audio u law is utilized in North America while a law is prevalent in Eu rope These algorithms are provided for compatibility with SIP style VOIP phones but don t provide much benefit over standard telephony in audio terms ACCESS Product Manual G 722 HE AAC HE AACv2 AAC LD AAC ELD G 722 This is a well known 7KHz medium fidelity algorithm used in some VOIP telephones and codecs It is provided for compatibility purpos es but is not considered a superior algorithm for audio codecs This algorithm is a highly regarded standard for compressing audio to critical listening standards It has been judged to produce near transpar ent audio at a coding rate of 128 kbps stereo The standard is a collabora tive of several audio companies best efforts and has become popular as the default audio codec of the Apple iTunes program AAC should be considered the highest quality codec in ACCESS Enhancements like HE AAC and AAC ELD attempt to maintain a similar quality and reduced bandwidth and delay This is a newer version of AAC defined for increased efficiency The goal of the algorithm is to produce AAC comparable quality at a lower bit rate It does this by encoding lower frequencies to AAC and higher frequencies using Spectral Band Replication SBR a technique that partially synthe sizes these high frequencies HE AAC is tradem
113. n domain 4 The server does not support the chosen codec 5 The called device does not support the chosen codec 6 The address is a POTS telephone number and POTS interworking is not supported 7 The address is a POTS telephone number and no credit is available most services charge for this ACCESS Product Manual ApvanceD N ACIP Topics The basic entries provided will allow support for the vast majority of N ACIP SIP based applications But there are inevitably situations where the defaults don t work and we ve provided some advanced options that can help As always these options are located in the Systems Settings and can be made visible by selecting the Advanced box 1 IP Port Universally SIP connections are supposed to use UDP port 5060 to negotiate calls between devices and between servers and devices Note this is only the negotiation channel actual audio data is passed on the RTP ports Changing this port number will change which incoming ports are used to initiate connections and to which ports connection re quests are sent Obviously the change must be made on both devices and this change will essentially make your codec incompatible with industry standard VoIP devices 2 RTP Port This is one of two port numbers used for audio data trans fer the port number directly above this is used as well Because this port number is negotiated at the beginning of a call over the IP port this port may be cha
114. ndependent programming down each channel ULB Default This profile is best for challenging IP connections It uses a very small bandwidth stream 14 kb s and delivers two way 7KHz mono voice audio Not useful for music For more details see the algorithms section 3G This mode is optimized for use over 3G wireless networks like UMTS EVDO and HSDPA Because 3G networks are usually asymmetrical they have higher download speeds this profile delivers a robust medium delay mono stream in the upload direction and two independent low delay mono streams in the reverse direction These two streams can be useful as separate program and cueing channels as an example BGAN Profile optimized for use over INMARSAT BGAN terminals This profile keeps the entire data stream beneath the limit for 32K streaming service which is the most economical mode for use on ACCESS This mode provides a robust medium delay mono stream in the forward direction and a low delay mono stream in the reverse direction POTS Profile used for connections over the modem card directly to other ACCESS or other Comrex POTS codecs not through the internet Linear PCM Profile used for sending and receiving Stereo uncompressed audio Linear PCM requires a large amount of network bandwidth and is generally not suitable for use on the public Internet Usable in LAN environments wired or wireless or with high speed IP radio links FLAC This profil
115. ndication of how much overhead is required for the various IP headers on each packet Frame Loss is also listed as an individual figure for lost and late packets This table also includes an estimation of how much delay is attributed to each end of the link This includes coding delay and buffering but does not include any delay being caused by the network Graphical representations of Jitter Buffer Manager activity and Frame Loss are also displayed 3 in Figure 22 The light blue area in the upper graph represents the jitter values over time The work of the Buffer Man ager is shown by the green line which is the target buffer delay that the system is trying to achieve based on measurements done over the jitter window 37 COMREX CORPORATION The lower graph displays a real time and historical representation of frame loss If the decoder does not receive packets in time the chart will show a red line indicating percentage of lost packets over the one second interval AUDIO METERING TAB The Audio Metering Tab as shown in Figure 23 provides a representa tion of Input and Output audio levels in several formats Each of these meters including the top section meters which are always visible may be turned On and Off individually All audio meters are defaulted to Off when ACCESS is first enabled This is because transfer of audio level informa tion consumes bandwidth on the local network as well as CPU cycles on the client computer
116. nged without breaking compatibility Note that many SIP stan dard devices use port 5004 for this function Due to the negotiation it is not important that these numbers match on each end Changing this port to 5004 can actually have an adverse effect since 5004 is the default port for other services on Comrex codecs 3 Public IP Override See the next section SIP TROUBLESHOOTING for more information on this option 4 Use STUN Server See the next section SIP TROUBLESHOOTING for more information on this option 5 SIP Proxy Keepalive Only applies to Registered mode This variable determines how often the codec phones home if registered with a SIP server It s important that the codec periodically ping the server so the server can find the codec for incoming calls It can be adjusted primarily to compensate for firewall routers that have shorter or longer binding tim ings i e the router may have a tendency to forget that the codec is ready to accept incoming calls and block them 93 COMREX CORPORATION SIP TROUBLESHOOTING OUTGOING CALL ISSUES INCOMING CALL Issues 94 6 SIP Domain Only applies to Registered mode This is the name of the network controlled by the SIP server This parameter must be passed by the codec to the server Under most circumstances this is the same as the servet proxy address and if this field is not populated that is the default If for some reason the domain is d
117. nk will disable this function ACCESS Product Manual BRIC NORMAL SETTINGS MODEM SETTINGS N ACIP SIP SETTINGS GUI Password Allows you to define a password for the web page login screen and firmware updater The default password is comrex lower case You can disable the remote control and firmware updating functionality completely by disabling the Remote Control option Enable Remote SSH Access Provides the ability for Comrex support to connect to this unit using the SSH protocol in order to troubleshoot We recommend leaving this option enabled since SSH access requires a key value that is not disclosed by Comrex generic SSH requests are rejected Accept Incoming Connections This determines if this ACCESS is to used for incoming normal IP connections If this function is not enabled ACCESS will only support outgoing calls using BRIC Normal Mode Modem Mode This setting determines which of the two POTS modes is to be used for incoming calls One limitation of ACCESS POTS Codec Modes is that both ends must be set correctly for POTS codec calls to work The default setting is POTS codec which causes ACCESS to answer incoming POTS calls that are compatible with ACCESS Matrix BlueBox and Vector codecs but not Hotline More information on may be found in SECTION 9 POTS Copec Connections The other option is Stereo POTS Stereo POTS Mode provides a stereo audio signal over a single dial up phone connection It ut
118. nt of a keyboard and VGA monitor to the device Alternately during the first five minutes of power up the IP parameters may be set by a PC on the local LAN using a proprietary broadcast UDP protocol Comrex provides the Device Manager application to perform this function on the local PC After five minutes of operation this function is disabled Firmware updates to the device are installed using the Device Manager utility software This update process is password protected and done via XML over TCP port 8080 In addition to the password protection the update data itself must have a valid cryptographic signature from Comrex or else it is rejected In order for the unit to be remotely updated TCP port 8080 must be forwarded to the device Alternately updates can be initiated from any local PC using the Device Manager application In its most commonly used mode the ACCESS codec delivers an RTP UDP stream from source port 9000 to destination port 9000 by default By default it listens for incoming RTP UDP streams on port 9000 To use the default mode only UDP 9000 needs to be forwarded to the device Alternately the device can be configured to deliver a similar TCP based stream on TCP port 9000 By default the device listens for incoming TCP streams on TCP 9000 This function may be disabled The source port of TCP streams is ephemeral and if an incoming stream is detected one will be returned to the ephemeral port The device also
119. onnections are defined by the ACCESS at the other end Network Remotes Stats Configure Available Profiles HQ1 Default 1 HQ2 Default HQ2 Stereo Default pn ULB Default Glen 3G 3G AAC ELD Copy BGAN pg BGAN AAC ELD 0 POTS AAC Mono AAC Stereo HE AAC Mono 1 HE AAC Stereo Set Default HE AAC V2 Stereo 1 AAC LD Mono AAC LD Stereo 1 AAC ELD Mono AAC ELD Stereo 3 Linear PCM FLAC Factory Profile Remove Si Q F1 Menu Arrows Enter Navigation a i Figure 16 Available Factory Profiles Several factory profiles are available and may not be edited by the user Here s a short description of the proprietary and less known encoding profiles HQ1 Default This is the default choice of profiles for new remotes It provides a low delay full duplex 15KHz mono audio channel over a small 28kb s data stream HQ2 Default Although this profile adds substantial additional delay it is extremely robust and performs well over connections that are prone to packet loss It provides 15KHz two way mono audio over small 24kb s data streams ACCESS Product Manual HQ2 Stereo Default This profile offers a stereo stream using only around 30kb s It has the same delay and robustness aspects as HQ2 default above The stereo stream created needs to have correlation between left and right channels i e you can not send i
120. ons if applied will be embedded into the stream To decode a stream open one of the supported players and find the option to open a URL based stream In Winamp and VLC input the address of the ACCESS in the following format http 192 168 0 75 8000 insert the real IP address but always use port 8000 In Windows media input the address like this http 192 168 1 75 8000 stream asx using the actual IP address of course ACCESS can stream while connected to another ACCESS in normal mode If the BRIC connection is using an AAC algorithm supported by players when a stream is requested it will be delivered using the same encoder as the BRIC connection regardless of the HTTP settings If the ACCESS encoder is Linear or FLAC the stream request will be rejected ACCESS Product Manual SeEcTION 15 ABOUT GATEWAY OPERATION CONNECTING AS A GATEWAY Gateway OPERATION Warning Advanced Topic ACCESS includes a special operational mode that allows it to share a net work connection with other devices ACCESS will create and maintain the main network channel then act as router over a second network port to deliver data to an external device ACCESS codec packets contain real time headers and the ACCESS will deliver these to the network ahead of other user information In this way ACCESS will assure that outgoing user data will not affect outgoing codec packets On the return channel priority of audio codec packets vs
121. ons are defined by the ACCESS at the other end Profile creation is segmented into commonly used and advanced options In order to simplify the interface Advanced Options are normally hidden from the user Remember building a profile doesn t change how any remotes are con nected until that profile is assigned to a remote on the Connections Tab Once a profile is defined it will be available on the Connections Tab to be assigned to any defined connection x E ACCESS GID GED FW 2 8 p13 FLASH GUI 2 8a Connections Statistics Audio Metering Profiles System Settings PROFILE PROFILE SETTING SETTING ADJUSTMENT aba Sanani General Profile Settings gt Hore ood These settings apply to the whole profile HQ2 Stereo Default gt amp Remote ULB Default 3G 3G AAC ELD PROFLE NAME BGAN HQ Default BGAN AAC ELD POTS AAC Mono AAC Stereo HE AAC Mono HE AAC Stereo denotes factory profile lt gt denotes default profile CHANNEL BRIC Normal Set Default Add New Profile Copy Profile Remove Profile FACTORY PROFILE Show advanced options CHAT Send Figure 24 Profiles Tab 39 COMREX CORPORATION BUILDING A PROFILE 40 We ll discuss the various profile options without the Advanced Options first and move on to the advanced selections in the next section To build a new profile select Add New Profile 1 in Figure 25 and a new profile appears on the list labeled New Profile
122. ot connected DISCONNECT Comrex Lab Music 70 22 155 132 not connected HE AAC Stereo POTS Test Line 9787841700 connected Rx POTS Mono 24000 ETRAI POTS connect 24000 bps Tx POTS Mono 24000 RETRAIN RATE DROP e Lessel Lessel Figure 34 Connections Tab During an Active POTS Call You can force the system to drop to the next lowest connect rate at any time by clicking the Rate Drop button at any time Audio transfer will be interrupted momentarily while the units negotiate the new connect rate Alternately you can force the system to initiate the entire training sequence 65 COMREX CORPORATION TROUBLESHOOTING POTS CONNECTION 66 again the chat sounds heard at the beginning of a call by clicking the Retrain button You will lose audio for a longer time approx 7 seconds but the modems will completely re equalize the connection and return audio when finished Once ACCESS has dropped to a lower rate either by rate drop or retrain from either end there is no way to force it to connect at a higher rate If you want ACCESS to try again for a higher connect rate you will need to disconnect the call and dial again There are dozens of factors that can affect the success or failure of a POTS codec call some within the user s control and some not Here s a short list of rules to follow for POTS codec connections 1 Use the POTS codec on a direct telephone company line and avoid in house phone systems A line us
123. ou will be prompted to input the Ethernet MAC address of the ACCESS you wish to add The MAC address is available via the touch screen under Network gt Configure Network or alternatively by scanning for the unit via the Device Manager PC based software utility The MAC address of the ACCESS must be inputted in a format with colons between each pair of characters Add New Unit lt Back to all Audio Codecs Unit MAC Address MAC Address Figure 40 Entering New Units 73 COMREX CORPORATION USING SWITCHBOARD TS 74 Once the unit s MAC address es are input correctly you will see them appear in the unit list as shown in Figure 41 The next time the properly configured codec goes on line it will sync with the server The codec name AAC status and other information will be updated Units Account Info Manage Groups Manage Zones Logout WCMX BRIC TS Units Units Owned By This Account Units Owned By This Account Unit Product Last Connect Product Type AA Delete Status Version 2012 05 09 ACCESS 00 01 c0 02 3b 82 00 01 c0 02 3b 82 2 8 p10 15 27 38 0 Portable 2012 05 21 00 40 63 e2 89 50 Paul Revere ACCESS Rack 2 8 p13 test4 12 17 24 0 ACCESS 2009 12 30 ACCESS 00 16 76 b5 38 ef SoftCodec 15 17 50 0 win32 2012 05 21 00 01 c0 0a cf 02 00 01 c0 0a cf 02 ACCESS arm2 12 52 14 0 Figure 41 Switchboard TS Main Account Screen Once Switchboard TS is enabled and you have correctly created your group on the
124. outgoing connection on ACCESS you must enter the info about remote connection into the Connections Tab This acts like a phone book saving the names and numbers of everyone to whom you connect As shown in Figure 27 ACCESS comes pre programmed with three connec tions Loopback is chosen when you wish to test ACCESS by connecting the local encoder and decoder together The other two entries are connections to Comrex in Massachusetts and these may be used for your testing when they re not busy with other users We maintain two CD players on these ACCESS feeding voice and music audio respectively ACCESS GD GD FW 2 8 p10 FLASH GUI 2 7 1e Audio Metering Connections REMOTE ACCESS UNITS Name Address Current State Receive Status Profile Last State Transmit Status Loopback 127 0 0 1 not connected Comrex Lab Voice 70 22 155 131 not connected Comrex Lab Music 70 22 155 132 not connected REGISTRATION STATUS TRAVERSAL SERVER STATUS DISABLED SIP STATUS ONLINE 200 OK PUBLIC IP ADDRESS 70 22 155 131 NAT TYPE Open Remove Stored Remote Change Remote Settings CHAT Send Figure 27 Connections Tab ACCESS Product Manual To create your own outgoing connection click Store New Remote 1 in Figure 28 to get the entry pop up Choose a name for the remote e g WXYZ followed by the IP address or phone number of the remote The next field is optional If the
125. re lost This is useful in applications where staying below a certain delay figure is essential but use of the delay limit can result in very poor performance if the network jitter dramatically exceeds the limit Fixed Delay This option simply sets the Delay Cushion and Delay Limit at a similar value so that the delay buffer is defined to the chosen value and will not increase or decrease significantly Buffer Management On Off This option is available only as a troubleshooting tool Turning the manager off will result in eventual failure since the manager is required to compensate for clock skew between the encoder and decoder The System Settings Tab defines parameters that are not specific to a particular remote connection Examples are how incoming POTS and IP calls are handled global modem settings and how the contact closures are assigned The System Settings Tab is shown in Figure 26a GID GD ACCESS GID CHED FW 2 8 p10 FLASH GUI 2 7 1e Connections Statistics Audio Metering Profiles System Settings SYSTEM SETTING SETTING ADJUSTMENT E System Settings F Traversal Server System Settings em Unit name and auto connect are configured here E Contact Closures 5 Aux Serial Settings 7 Security Settings gt BRIC Normal Settings UNIT NAME gt DN Modem Settings lt 1 gt N ACIP SIP Settings ALWAYS CONNECT TO REMOTE Do not autoconnect M lt 2 _ Show advanced options el N Apply Set to Defaul
126. remote has password filtering enabled for in coming calls you will need to enter that password into the next field case sensitive in order to make a connection to it see Passworp FILTERING in the next section for further information If no password is required leave this blank GD GD ACCESS GD CHMOD FW 2 8 p10 FLASH GUI 2 7 1e Connections Audio Metering Profiles System Settings REMOTE ACCESS UNITS Name Address Current State Receive Status Profile Last State Transmit Status Loopback 127 0 0 1 not connected 1 STORE NEW REMOTE not connected REMOTE NAME Ne not connected IP ADDRESS OR PHONE NUMBER CONNECTION PASSWORD REGISTRATION STATUS TRAVERSAL SERVER STATUS DISABLED PROFI SIP STATUS ROE ONLINE 200 OK Shoutcast PUBLIC IP ADDRESS 70 22 155 131 Cancel OK NAT TYPE aya em Open ES ES Store New Remote Remove Stored Remote Change Remote Settings Figure 28 Store New Remote in the Connections Tab Finally you will need to choose a profile to use when making these con nections ACCESS includes several common default profiles to choose from each of which enable a simple full duplex link using one of the avail able algorithms If you wish for a more complex feature set when making this connection you will need to click over to the Profile Tab and set up a specific profile using your cus
127. rent encoder modes 1 Loopback Allows for connection between encoder and decoder in the same system 2 Comrex Lab Voice Allows testing back to the Comrex headquar ters in Massachusetts USA 3 Comrex Lab Music This additional user provides a music feed from the Comrex lab ACCESS Product Manual STATISTICS TAB 2_ _ The Channel Statistics field 1 in Figure 22 delivers information on the total number of bits entering or leaving the ACCESS including multi ple connections if applicable IB UDP and RTP packet headers and coded audio GD Gm GD CTD FW 2 8 p13 FLASH GUI 2 8a Connections Statistics Audio Metering Profiles System Settings ACTIVE CONNECTIONS Remote Unit Duration RXRate RX Overhead RXDelay TXRate TX Overhead TXDelay Frame Loss Remote Loss Loopback 00 00 9 29 kbps 17 1kbps 36 19ms 29 kbps 17 1kbps 36 50ms o o CHANNEL STATISTICS lims Channel RX Rate TX Rate Target BRIC Normal 7 8kbps 7 8kbps Delay Jitter a 1 Delay Oms T 60 T 30 seconds TO 100 75 Correction 50 Remote Loss Rate Frame Loss Rate 0 T 60 T 30 seconds TO CHAT Send Figure 22 Statistics Tab The Active Connections box 2 in Figure 22 breaks this information down further Because ACCESS is capable of more than one simultaneous connection in some modes each connection is listed independently Receive Rate and Transmit Rate are listed along with an i
128. ressed Indicates several states of Ready Off Network ready not connected to remote Red Network unavailable Green Connected to remote Yellow Connected to remote but no network i e network connectivity lost during connection Slow Red Blink Software update in progress Fast Red Blink Displaying unit IP address ACCESS uses its left channel input only for Mono Modes Right channel is ignored Output audio is available at both the left and right outputs in Mono Mode ACCESS audio connections are balanced professional level inputs and outputs Table 1 XLR Pinout Table 2 AES3 Pinout 11 COMREX CORPORATION Pinouts Contact Crosure Contact closures are available via the male 9 pin D connector on the back of the ACCESS Rack Inputs are triggered by shorting the respective input to Pin 5 Outputs consist of an open collector circuit which when inac tive will offer a high impedance path to Pin 5 and when active will offer a low impedance path to Pin 5 These outputs are capable of sinking up to 200mA at a voltage up to 12V Do not switch AC mains power using these contacts Table 3 Contact Closure Pinouts PinourTs SERIAL PORT The Serial Port is capable of transferring ancillary data to the far end of the connection By default the communication parameters are set for 9600bps no handshaking no parity 8 data bits one stop bit 9600 n 8 1 It is pinned on a 9 pin D female in DCE style pinning The port
129. restart the Rack s computer board Attach an analog telephone line here for POTS codec compatibility Four sets of contact closure inputs and outputs are available on this port These can be used to send signals to the far end of the link or to trigger remote control gear such as automation equipment Attach a PS 2 compatible mouse or keyboard here for use with the console connection interface 10 100BaseT Ethernet port for connection to your network Available for use with USB keyboards and mice May also be used with some 3G USB wireless modems ACCESS Product Manual Figure 2 Front Panel Diagram and Descriptions 19 16 SEND 17 RECEIVE 18 RESET 19 STATUS Mono vs STEREO PINOUTS AUDIO 3939333339993 33339933 3 0 Seno P ACCESS d d t 1 17 i 18 Peak meter that displays the level of audio being sent locally into the ACCESS regardless of whether or not a connection is active Proper level is indicated by peaks driving the Yellow LEDs while avoiding lighting the Red LEDs which indicates clipping Peak meter that displays the level of audio being sent remotely when a connection is active Proper level is indicated by peaks driving the Yellow LEDs while avoiding lighting the Red LEDs which indicates clipping Adjustments to this level must be made on the far end of the link Recessed button to send ACCESS into hardware reset mode Approximately 30 seconds are required to reboot when this is p
130. rts open to allow calls to be established correctly Also port forwarding may be required to accept calls if your codec is behind a router In reality most VoIP calls involve a server used as an intermediary for the ACCESS Product Manual handshaking But we believe most codec calls will be handled directly and SIP supports both techniques so we ll ignore the topic of a SIP server here The main area where SIP complicates matters is in how an audio channel gets established once the handshake channel is defined In the common sense world the call would be initiated to the destination IP address then the called codec would extract the source IP address from the incoming data and return a channel to that address In fact that s how the default mode of Comrex codecs work and it works well But SIP includes a separate forward address or return address field and requires that a codec negotiating a call send to that address only And this works fine as long as each codec knows what it s public IP address is Outgoing Call Issues A unit making an outgoing call must populate the return address field But any codec sitting behind a router has a private IP address and has no idea what the public address is So naturally it will put its private e g 192 168 x x style address into that return address field The called codec will dutifully attempt to connect to that address and undoubtedly fail since that can t be reached from t
131. s server or of its function Comrex reserves the right to discontinue availability of this service at any time Comrex also reserves the right to remove any account from the server at http switchboard comrex com at any time for any reason In no way shall Comrex be liable for this server s malfunction lack of availability or any resultant loss therein The software that runs the Comrex Traversal Server on the Internet is available from Comrex in an executable format free of charge with basic instructions on how to set it up The address of the server used for these functions is configurable in the codec firmware If you wish to deploy your own Traversal Server contact Comrex for details on obtaining this software Comrex is not liable for training or support in setting up a TS server and the software is available without warrantee or guarantee of suitability of any kind ACCESS Product Manual Section 20 SUPPLIERS DECLARATION OF CONFORMITY CONFORMITY AND REGULATORY INFORMATION Place of Issue Devens Massachusetts Date of Issue January 23 2006 Comrex Corporation located at 19 Pine Road Devens MA in the United States of America hereby certifies that the Comrex ACCESS Rack bearing identification number US DXDMDO1BACCRK complies with the Federal Communications Commission s FCC Rules and Regulations 47 CFR Part 68 and the Administrative Council on Terminal Attachments ACTA adopted technical criteria T
132. st be able to support these streams For example if your encoder runs at 35 kbps network utilization sending to two locations will require 70 kbps upload speed from your network Multi streaming should not be confused with IP Multicast which is de scribed in the next section Each ACCESS can also run only one decoder So it s important that in a multi stream environment a maximum of one stream is sent in the reverse direction This means that users interested in hearing a multi stream must turn off their encoders This can be a bit confusing because multi streams can be initiated from either end of the link Figure 44 shows an ACCESS multi stream arrangement ACCESS A is the multi streamer with ACCESS B C and D listening to the same audio In order to set up a multi stream scenario you will need to know how to turn ACCESS encoders Off This must be done by building a profile with either the Local or Remote Transmitter mode set to Off as shown in Figure 48 User C Receiving BRIC HQ1 Mono gt f User D Receiving BRIC HQ1 Mono Figure 48 Multi Streaming Arrangement We ll give two examples of multi steaming scenarios The first is an envi ronment where the ACCESS that is serving the multi stream initiates the calls and in the second the serving ACCESS accepts all its incoming con nections ACCESS Product Manual CCESS FW 2 8 p13 FLASH GUI 2 8a Connections Statistics PROFILE PROFILE SETTING
133. supports transmitting and receiving UDP multicast streams using UDP port 9002 unless another port is specified by the user This is not enabled by default and a configuration must be explicitly created and connected on both ends for this function Multicast streams are inherently unidirectional and the configured port must be forwarded to the device on the receiving end The multicast TTL value defaults to 1 for in network multicasting but may be changed to any valid TTL by the user 115 COMREX CORPORATION 116 Outgoing ports and incoming ports may be altered via the User Interface For compatibility with other industry devices the ACCESS also listens for incoming streams and can place outgoing streams on UDP 5004 and 9150 The device also listens for incoming SIP connections on UDP port 5060 and in the case of successful negotiation will transfer audio on UDP ports 5014 and 5015 lt 6014 and 6015 with 3 0 firmware gt These ports may be changed via the user interface and these functions may be disabled The device has the ability to act as a streaming server accepting TCP connections on port 8000 and delivering streaming data This function is disabled by default and the port number may be changed The device has an optional STUN server and directory download function Switchboard TS In order for this function to work the device must be allowed to create an outgoing TCP socket from port 8082 As part of the STUN protocol
134. t autoconnect _ Show advanced options Apply Set to Defaults Software Licensing CHAT Send Figure 32 24 7 Operation in the Connections Tab ACCESS Product Manual SECTION 9 POTS CODEC SET UP FOR ACCESS COMPATIBILITY Usinc ACCESS WITH POTS POTS PLa OLD TELEPHONE SERVICE Conec CONNECTIONS ACCESS is capable of connections over modem links This mode emulates the function of Comrex POTS codecs which have been used for years to deliver high quality audio over normal dial up telephone lines This mode provides for a point to point connection between the codecs i e no in ternet access is used and the call is placed directly from one ACCESS or legacy codec to the other In the current firmware ACCESS is capable of connecting over dial up phone lines to ACCESS Codecs Comrex Matrix Codecs Comrex BlueBox Codecs Comrex Vector Codecs Note Backward compatibility to Hotline codecs is not supported The legacy codecs Matrix Vector or BlueBox must be configured for operation in Music Mode which will allow full fidelity up to 15 KHz con nections Voice Mode is not supported by ACCESS Contact closures and ancillary data supported by legacy codecs are not supported by ACCESS ACCESS requires that outgoing POTS connections be defined on the Con nections Tab When defining any outgoing connection a profile must be assigned to it For POTS Codec compatible connections the factory default P
135. t defines several mandatory encoding algorithms and the transport layer that could be used on them for compatibility For the most part the transports are straightforward and reasonable to implement and should interoperate It should be noted that several mandatory algorithms like G 711 G 722 and MP2 were included which provide little benefit to IP codec customers Comrex has declined to include MP2 which makes our codecs technically in violation of the standard But the most complex part of the standard was the decision on how to arrange Session Initialization which is the handshake that takes place at the start of an IP codec call The most commonly used protocol is called SIP which is used extensively by VoIP phones and therefore was a logical choice But SIP isn t terribly simple and has some drawbacks which will af fect codec operation We ve built into Comrex codecs several work arounds to reduce these limitations but understanding how best to utilize them requires that you understand what the limitations are Sipping Slowly In a nutshell SIP establishes a communication channel from the calling device to the called device on port 5060 All handshaking takes place over this channel and a separate pair of channels is opened between the devices one to handle the audio and the other to handle call control The original communication channel is terminated once the handshaking is complete Note that firewalls must have all three po
136. ted will be displayed on the top bar of the Remotes List The choices are 1 Open No NAT detected unit sees the Internet directly 2 Symmetric NAT or FW The most challenging type of router or firewall for codec connection purposes If both ends are behind this type of system and no port forwarding is applied connections will not work 3 Full Cone Restricted or Port Restricted NAT Switchboard TS can usually work around this type of router allowing calls to be placed in both directions 4 UDP blocked No normal codec connections are possible through this router To make calls with the help of Switchboard TS simply click one of the entries with the orange TS icon or shaded entry in the Web based Interface and click Connect Switchboard TS will handshake with the remote unit and make the connection automatically 75 COMREX CORPORATION CREATING USERS CONTACT LISTS 76 In some situations you may wish to create additional Switchboard users who can access the server web interface You can do this via the Users tab at the top of the main codec list This allows you to create accounts for users that can later be deleted if no longer desired As shown several user accounts can be created with unique passwords Franklin Roosevelt Comrex User has been added to your Account Add New User Name Username Email Phone Franklin Roosevelt Franklin franklin ww2 com ern Josef Stalin Josef josef ww2 ru Ea
137. testing You may add to this list by pulling down the Remotes menu and selecting Add New Remote This display is shown in Figure 9 You will need to input a name for this remote which can be anything as well as the destination IP address or phone number for a POTS call Finally you must choose one of the pre defined profiles to dictate how each direction of the connection behaves Several factory defined profiles exist for commonly used configurations and you can create your own described in the Console Connection Interface CONFIGURE Tas section Optionally you may add a password to this outgoing remote for connection authentication In this case the incoming ACCESS must also be programmed with the matching incoming password Network Remotes Stats Configure Add New Remote General IP Phone Password Settings Profile Profile Default Profile Backup Behavior Backup Remote No backup Automatically fall forward g Q Fl Menu Arrows Enter Navigation Figure 9 Add New Remote Screen ACCESS Product Manual Finally you may specify how the unit is to behave when connection is lost to this remote see Backinc Up A Connection in the Web based Interface section Once a connection is added it will appear in the main remotes list Return to the list by selecting Remotes and then Manage Connections If you expand your chosen remote with t
138. tom parameters Custom options can include one way transmission different encoders in each direction specialized packet arrangement etc Once defined on the Profile Tab the new pro files will be available in the Profile select window and they can be assigned to a remote connection 55 COMREX CORPORATION DISCONNECTING PASSWORD FILTERING 56 Once your remote connection entry is correct it s simply a matter of point ing and clicking to connect and disconnect a remote When a connection is attempted the Current State value in the connection table will change to reflect the progress of the connection If the connection fails the rea son for failure will be shown in the Last State category If it succeeds the encoder and decoder mode will be reflected in the Transmit and Receive Status columns Disconnecting is just as simple Highlight the desired connection and click Disconnect to end the connection Warning Advanced Topic ADVANCED CONNECTION OPTIONS The Connection Password function can be used to filter incoming BRIC IP connections but not POTS calls Using this function attempted incom ing connections will be rejected if they do not know the proper case sen sitive password For outgoing connections the password is entered when the remote connection is created on the Store New Remote menu 2 in Figure 28 For incoming connections the password is set on the System Settings Tab 1 in Figure 29 There isn
139. tored to the decoder For most applications like remote broadcasting it s useful to simulate a connection oriented stream so ACCESS uses a low bandwidth sub channel to deliver information back to the encoder about overall connection status It does this in its application layer rather than the transport layer where UDP exists By default it monitors the health of a connection and if no data is detected as received by the decoder for 60 seconds this is a user adjustable timeout it tears down this connection and goes back to idle state This can give an indication to the user that the network has failed and it s time to look at the problem The good thing about having the connection protocol in the application layer is that its use is optional For 24 7 operation there s no advantage to having the connection end if no data is received for a timeout interval So to set ACCESS for 24 7 operation several parameters are changed 1 The timeout value is set to infinity the connection will never be torn down regardless of data status 2 ACCESS is configured to re establish the connection in the event of a power up 3 The local Disconnect control is disabled The Disconnect function on the receiving side is still enabled but will result in an immediate reconnection by the initiating side 61 COMREX CORPORATION SETTING ACCESS FOR 24 7 OPERATION 62 As shown in Figure 32 using the Web based Interface 2
140. trol ACCESS Rack 00 40 63 e7 2b 8c 00 01 c0 04 a8 ae Figure 47 Share a Device The share creation screen allows you to choose a subset of your fleet for this share After you make your selection you ll need to enter either the name of the account you wish to share with or the email address of the administrator of the account it must be the one they used to create their Switchboard account An email will be sent from the server asking the user to confirm your Shares Once the Shares are confirmed your shared devices will appear as options in the external user s contact list menu This is important Shares do nothing until the external user adds them to a contact list If the user has only a single default contact list for his fleet he must still manually add your codecs to that in order for them to be visible to his fleet Finally if you want to temporarily deactivate a share this can be done by editing the share entry A tick box on the bottom allows activation deactivation of a share without the need to delete it or re invite users ACCESS Product Manual SEcTION 11 ABOUT THE ALGORITHMS ACCESS contains several different types of encoders and decoders for use on networks BRIC HQ1 This encoder decoder provides 15 kHz voice music transmission with HicH Om 1 extremely low delay and low network utilization It supports mono stereo and dual mono Here are some details of BRIC HQ1 e Low Delay BRIC HQ1 us
141. ts Software Licensing CHAT Send Figure 26a System Settings Tab ACCESS Product Manual GD CHED KI ACCESS GD GD FW 2 8 p10 FLASH GUI 2 7 1e Connections Statistics Audio Metering Profiles System Settings SYSTEM SETTING BE SETTING ADJUSTMENT sion saute Contact Closures Bi versace Server Contact closures are configured here E Contact Closures F Aux Serial Settings E Security Settings gt BRIC Normal Settings AUTO CONNECT ON CONTACT CLOSURE gt Modem Settings Normal Operation CONTACT CLOSURE INPUT 1 3 gt N ACIP SIP Settings Normal Operation w CONTACT CLOSURE INPUT 2 Normal Operation v CONTACT CLOSURE INPUT 3 Normal Operation CONTACT CLOSURE INPUT 4 lt 4 Activate contact closure 4 output when connected _ Show advanced options Apply Set to Defaults Software Licensing CHAT Send Figure 26b System Settings Tab The Systems Settings Tab has several categories System Settings Tra versal Server Contact Closures Aux Serial Settings Security Settings BRIC Normal Settings Modem Settings and N ACIP SIP Settings As with the Profile Tab basic options are shown by default Less used options are hidden until the Show Advanced Options box is clicked Unit Name Users are encouraged to name their codecs here The default name of a codec is the unique MAC address of the Ethernet port By changing this to something familiar and uniq
142. ual RATE DROP Vs RETRAIN Incoming unit settings usually the studio unit The incoming unit will receive the call from the field In this case the ACCESS must be con figured to treat all incoming calls as POTS Stereo Mode This is done in the System Settings section by selecting Modem Mode under Modem Settings To receive stereo calls this setting must read Stereo POTS To receive calls from older Comrex POTS codecs or ACCESS configured to emulate them the setting must be POTS Codec When incoming or outgoing POTS calls are active the Connections Tab changes slightly You will see two additional buttons appear on the tab la beled Retrain and Rate Drop These are special functions applicable only to POTS calls so they are not visible during IP connections The Connection Tab display contains two user controls Rate Drop and Retrain 1 in Figure 34 These controls are similar in function to those provided on POTS codecs ACCESS will initially connect at the best data rate supported by the telephone line and will display that connect rate on the Connections Tab page GID GD ACCESS GID GD FW 2 8 p13 test4 FLASH GUI 2 8a Connections Statistics Audio Metering Profiles System Settings REMOTE ACCESS UNITS Name Address Current State Receive Status Profile Last State Transmit Status Q Loopback 127 0 0 1 not connected SY NNES AAC Stereo Comrex Lab Voice 70 22 155 131 n
143. uct Manual Locat amp REMOTE SETTINGS BRUTE RELIABILITY OPTIONS If you ve chosen an IP based channel such as BRIC Normal then you ll be presented with two categories of options Local and Remote You ll use the Local Settings to determine how your ACCESS behaves and the Remote Settings will determine how the ACCESS on the far end behaves Each category lists identical options so we ll cover only the Local Settings Connection Timeout Under normal circumstances a connection will be terminated on one end and the other end will drop the connection in turn But if a network failure occurs or a connection is ended abruptly e g killing power to an ACCESS the system will drop the connection after a pre determined time The default is 60 seconds but this can be shortened or lengthened here If an indefinite connection is required see SECTION 8 OPERATING ACCESS 1N A 24 7 ENviRONMENT for additional information Encoder It s not necessary to define any decoder types when using ACCESS because they automatically adapt to the incoming stream Using this menu you can select the encoder used to send audio from this ACCESS local as well as the encoder used to send audio to this ACCESS remote The default value of the remote encoder is to follow the local encoder i e it will send exactly the same codec mode it receives This is defined as Follow Mode in the remote encoder selection table See Asour THE ALGORITHMS section
144. ue e g roving reporter weather guy etc this name is reflected in several places 1 In the browser used to show the remote control page 2 In Comrex provided utility software such as Remote Control and Device Manager 3 In Switchboard TS Buddy lists See Traversal Server Section 49 COMREX CORPORATION CONTACT CLOSURES AUX SERIAL SETTINGS SECURITY SETTINGS 50 Always Connect to Remote 2 in Figure 26a shows the system Auto Connect options Remote connections must be created in the Connec tions Tab before they can be assigned to any of these functions One field is available to designate a remote for always on operation This is useful in nailed up environments where a signal is required across the link 24 hours a day To assign an always on remote simply pull down the menu and select which remote to designate as Always On A connection will be made and sustained to the chosen remote The Auto connect on contact closure fields 3 in Figure 26b define auto connect rules for remotes to be triggered by the four external triggers available on the rear panel of the ACCESS Note These inputs are shared with the end to end contact closure signals so if a remote is designated as Auto Connect on a closure that closure signal is sacrificed in the di rection from this ACCESS To assign a remote connection to a contact closure simply pull down the menu box next to the desired closure and select the proper remote A
145. user name on the SIP account this is usually the dialing address 3 The password on the SIP account Fig 53 shows where this information can be applied in the systems setting section You will also need to enable the Use SIP Proxy option in that menu e e lt ACCESS CIID ACCESS Gm Gz FW 28 p13 lesl FLASH GUI 28a FW2 8 p13 FLASH GUI 28a Ces o o Ces sy sos Comecon zm 1 woen ru sem segs SYSTEM mme eme ADJUSTMENT REMOTE ACCESS UNIS fem Settings jame Address vurrent State jeceive Status 7 System Setir siP Proxy Address N Ada Current Stat Receive Stat I traversal Server EEN Profile Last State Transmit Status ONN Loopback 127 0 0 1 not connected V CURE Se Come Lab Voice 70 22 155 131 not connected gt Modem Settings Vie d Wee See S Come Lab Music 70 22 155 132 not connected Ni cceplincoming connections P sipiplelorg E SIP Proxy Address E SIP Username E sir Password show advanced options Software Licensing ACCESS Rack 74 94 151 150 9000 not connected REGISTRATION STATUS BRIC Link 74 94 151 149 9000 not connected TONING Ste ap status Lab Music 70 22 155 132 9000 not connected E PUBLIC IP ADDRESS 70 22 155 131 NAT TYPE Open Apply Sel fo Default Store New Remote Remove Stored Remote Change Remole Settings Chal Figure 53 N ACIP SIP Settings Send Figure 54 SIP Status Once this infor
146. verview is available in our product manuals What is all this about Comrex codecs and many other brands have a set of nifty protocols that allow easy IP connections between units So easy in fact that we don t even recommend reading this paper unless you have a need to communi cate with non Comrex products But many users are concerned about getting locked in to a certain codec brand So an international committee was formed by the European Broad cast Union called N ACIP to hammer out a common protocol to inter connect codec brands This committee resulted in the establishment of EBU3326 a technical document describing how best to achieve this goal EBU3326 by and large establishes a set of features each codec should sup port then leaves most of the heavy lifting to other previously established standards like SIP IETF RFC 3261 Topics not covered yet by EBU3326 101 COMREX CORPORATION 102 include things like carrying ancillary data and contact closures from end to end codec remote control and monitoring and NAT traversal which at this point are still left to the individual manufacturer s discretion So if these topics are important to your application it s best to stick to a single codec vendor and their proprietary protocols More about EBU3326 The saying goes that a camel is a horse built by a committee and true to form EBU3326 has some elements that make things frustrating and com plex The documen
147. ving ACCESS accepts all incoming con nections all the profiles are built on the Remote Receivers ACCESS B will use a simple profile by defining the encoders in each direction and assign it to ACCESS A ACCESS C and D will each define a profile with their Local Encoders turned Off and assign them to A ACCESS B should connect first When C and D connect they will hear the same stream as B regardless of how their remote encoders are set in their profiles In a multi streaming environment the first man wins For example the first connection made between units will determine the encoders used for all others After the first full duplex connection is made all other attempts at full duplex connections to either end will be rejected 83 COMREX CORPORATION SEcTION 13 MULTICAST PROFILES 84 IP Mu Lticast Warning Advanced Topic IP Multicast is an efficient way of delivering ACCESS digital audio streams to multiple locations This involves relying on the network to distribute the stream to the locations that require it rather than creating an indepen dent stream for each user IP Multicast requires the use of an IP Multicast capable network The commercial Internet with few exceptions is not capable of supporting IP Multicast Some private LANs and WANs are IP Multicast capable IP Multicast supports only a single direction stream An IP Multicast encod er can not receive input streams In this manual we assume that
148. w much delay to install in front of the decoder to achieve uninterrupted audio It does this by creating a statistical analysis of the amount of jitter experienced over a fixed interval of time the window and making a judgment based on other parameters like the decoder s resiliency to errors This is actually a very complex decision making process involving many variables and most of the time the default parameters should work well The Advanced Decoder options are a means to override these defaults and changing them should be done with care The following advanced options affect the Decoder Retransmit Squelch These options are used to determine how the buffer manager reacts to typical data dropouts like those seen on wireless networks Some explanation Many wireless networks have their own layer of data protection riding on top of any other data layer providing packet retransmissions in the event of signal fade The symptom from the network standpoint is that data will come to a stop for some period of time while the signal is faded and the network will buffer all packets during this time Once the wireless link is restored all the buffered packets will appear to the decoder as if they were simply very late In essence the protection layer will fight the buffer manager The effect will be that the buffer manager will expand the buffer increasing delay dramatically without any benefit The Retransmit Squelch allows the decod
149. which is the same principal utilized in many digital mobile phones The dif ference is that while mobile phone vocoders typically provide about 3 kHz audio bandwidth BRIC ULB delivers more than twice that fidelity providing a much more listenable and less fatiguing sound BRIC ULB is optimized for human voices It does a respectable job of encoding background noise and crowds but music tends to suf fer rather dramatically on BRIC ULB e Mono Only a single audio channel is supported on BRIC ULB e Dynamic Data Rate The BRIC ULB encoder adapts its out going audio frame size based on the complexity of the incoming audio This encoder does not compress audio at all It uses a 48 kHz sampling rate and simply applies small frames of linear audio to IP packets This mode is only useful on high bandwidth LAN or managed WAN environ ments Mono Mode requires a network capacity of 768 kbps while Stereo Mode requires a network bandwidth over 1 5 Mb s This encoder compresses the audio data using a lossless algorithm This means that the audio extracted from the decoder is identical to the audio input to the encoder with no coding artifacts FLAC typically removes 30 40 of the network data compared to Linear PCM but the actual data rate is variable and is based on the complexity of the coded audio Using FLAC over Linear PCM typically results in a slightly higher 5ms overall delay G 711 u law and a law These are the coding algorith

ACCESS Rack Product Manual

Contents

Download Pdf Manuals

Related Search

Related Contents