Towards developing secure video surveillance systems over IP
Contents
1. redundancy Still to the best of our efforts we were unable to find failure data for surveillance cameras although such data can be easily found for many other components 14 C Authenticity In order to assure authenticity for the information the use of cryptographic techniques is mandatory and is the only way to assure that images indeed originate from the video surveillance system and are not injected by some adversary This is also acknowledged by research papers and general books on the subject 4 For this purpose the first cryptographic solution is the use of digital signatures however these cryptographic primitives are expensive as shown in table 1 Also the use of secure point to point connections such as the SSL is not a good alternative as the same images needs to be sent to many users which will require different encryption keys and will require for the sender to encrypt the same message under each distinct key thus causing overhead on the sender s side Still authenticity can be assured at a cheaper price by the use of MAC codes However MAC codes require a secret shared key which is not practical in a setting with many receivers Fortunately there is a good solution to overcome this by the use of time synchronization a single MAC key can be used for all users The first proposal for this was the TESLA protocol which can be found in several variants 6 7 8 In the context of the AAA framework we believe that TE2. un trusted server while the user was trying to access the camera from a different network Also when users are added through the web interface from a remote computer new user names and passwords are sent in clear text and can be easily captured Therefore adding new users is insecure gt Confidentiality vulnerabilities In the same setting we were able to capture packets sent from DCS 900 with Wireshark and to reconstruct the sent images from these packets It easy to spot the jpg files sent from the camera as jpg files start with OxFFD8 and end with OxFFD9 Therefore DCS 900 does not assure any confidentiality for the communication gt Authentication vulnerabilities As stated previously user passwords can be extracted in certain situations while password based authentication itself does not offer a high level of security Also no authenticity information for the transmitted pictures seems to be embedded it is almost clear to us that packets can be replayed or replaced by an adversary and it remains as potential future work to try this As a partial conclusion on the DCS 900 we can state that it behaves well with respect to accessibility as it allows remote access via a web interface by any remote device that supports Java or ActiveX However the system is vulnerable with respect to the objective of authenticity as there is no authenticity on the broadcasted images Even with respect to availability the system may be vulnerable as
3. an adversary may be able to eavesdrop and capture the admin password if the camera is not properly configured as stated previously and simply stop the camera from broadcasting thus causing a DoS Wide Area Network S A Surveillance Area B Local Area Network e A Local stations 192 168 0 x ie F Figure 1 Application setting for the DCS 900 camera IV THE PROPOSED SYSTEM A Outline of the system The scenario that we address is depicted in figure 2 It consists in a camera that broadcasts images to a number of receivers A video cryptographic module VCM is used to communicate with the camera Only the VCM is forwarded over the WAN For the moment the VCM was implemented as a server application in Java and runs on a standard computer However it remains for us as future work to implement this on a single board computer SBC or on a FPGA board that can be rack mountable in order to obtain a handier device The VCM is mainly responsible for assuring authenticity The VCM is also flexible and allows connection of different kinds of cameras that are connected over RJ45 or USB connectors as well The cryptographic protocol for assuring authenticity is based on MAC codes and time synchronization similar with the TESLA protocol 7 The application from the VCM provides time synchronization as well however it is better if time synchronization is not provided by the VCM as synchronization requires one
4. digital signature which is more computational intensive and can be exhausted to cause DoS For this purpose external time servers may be used as well Now we outline the characteristics of the proposed system in the introduced AAA framework gt Accessibility Both the client and server parts are implemented in Java which is architecture independent Because of this we were able to run the client parts of the application on standard computers PDAs and mobile phones The client is a stand alone application however it is also possible to develop an applet that runs in a browser as the DCS 900 camera does gt Availability Threats against protocol availability are partially removed by the fact that it is a broadcast protocol and the sender does not get additional requests from the receivers that consume resources except from sending the images which are embedded in a packet that is the same for all receivers This also removes the drawback that each new receiver consumes new sender s resources as would happen if the images are encrypted or authenticated with a different key for each receiver which will linearly increase the computational overhead However more serious DoS attacks can take place on the sender in the synchronization stage as the sender is required to compute a digital signature that is more computationally intensive To see how much computational time it will take to make time synchronization a comparison betwee
5. the TESLA protocol We previously used a related solution on mobile phones 3 which proved to be efficient This makes the i th key from the key chain equal to k x 46 modn and by using a time memory trade off each key can be computed at the reduced cost of one modular multiplication The advantage in this construction of the key chain is that it allows us to broadcast for an unbounded period of time in contrast to hash chains which exhaust and must be re initialized The protocol has the following send stage used for all receivers Send Stage VCM Receivers P limage MAC kor image ra 1 7 In order to allow receivers to receive images at a desired frame rate the protocol is modified in the following way in the synchronization stage each receiver will also send a constant which establishes the frame rate as a multiple of the broadcast rate of the server Thus each receiver can choose its own frame rate and this choice depends mostly on its computational power and bandwidth This is resumed in the following Synchronization Stage Receiver VCM Nonce r VCM p 2 broadcast current VCM Receiver Nonce r t TIE ig The actual frame rate for the receiver will be l frame rate an Here denotes the current time on r the VCM and t broadcast is the key disclosed in the current time denotes the time at which broadcast was started k current interval All these v
6. SLA like protocols are the best alternative IHI BRIEF ANALYSIS OF THE DCS 900 IP CAMERA A brief analysis of the DCS 900 11 security camera a popular camera from D Link may be useful DCS 900 has nice features it is easily configurable via a web interface and comes at a reasonable price On line captured images may be viewed from a browser that supports Java or ActiveX However with respect to some serious security levels it does not provide good enough characteristics for a surveillance system and is nothing more than a toy that will be easily breakable by an adversary We enumerate some of its weaknesses gt Password length vulnerabilities For the Revision A variant the camera manual specifies that user authentication to the camera is done by an 8 character password from the printable ASCII set 1 e 94 characters This is roughly the equivalent of a 52 bit key which is not a sufficient security level for today More as these passwords are chosen by users they can be subject to dictionary guessing attacks as well This restriction is not stated in the Revision B manual but the web interface for the Revision B camera that we have does not allow us to introduce passwords larger than 8 characters so the restriction is the same Also if from the setup wizard for Revision B a passwords larger then 8 characters is set then the password is not recognized at the login via the web interface More if you enter just the first 8 characte
7. The rows from table 1 correspond to the following 1 Intel Core 2 Duo 6800 at 2 66 Ghz Desktop 2 Intel Core 2 T 2300 at 1 66 Ghz Notebook 3 4 Fujitsu Siemens Pocket Loox and Asus MyPal A 696 both with Intel PXA270 312Mhz processors PDA 5 Nokia 6288 Mobile Phone Also we tested different implementations of cryptographic functions from NET Java and Bouncy Castle API 10 13 and in tables 1 and 2 only the most relevant results are shown The results show that hash functions and MAC codes can be computed in the order of micro to milli seconds and therefore are affordable for our scenario Still 1024 bit modular exponentiation with 1024 bit exponents which is the basic operation of an RSA digital signature is in the order of seconds which may be too expensive Also there seems to be some implementation problem with the Bouncy BigInteger class in C as modular multiplication is with one order of magnitude more computational intensive then modular multiplication with the BigInteger class in Java as results from tables 1 and 2 show However the verification procedure for a digital signature is more efficient and in the simplest case may be in the order of a few modular multiplications according to the size of the public exponent The advantage in developing a remote access video surveillance system is that while working with a client server application different platforms can be used for implementation on the client and s
8. Towards developing secure video surveillance systems over IP Bogdan Groza Ioan Silea Politehnica University of Timisoara Faculty of Automatics and Computers Timisoara Romania bogdan groza aut upt ro 1oan silea aut upt ro Dragos Pop Continental Corporation Infotainment and Interpersonal Department Timisoara Romania dragos pop continental corporation com Victor Valeriu Patriciu Military Technical Academy Department of Computer Engineering Bucharest Romania vip mta ro Abstract A framework of three attributes for video surveillance systems is underlined availability accessibility and authenticity Under this framework a scenario in which surveillance cameras can be accessed by remote devices such as mobile phones PDAs over IP is addressed Some security drawbacks of an off the shelf product are depicted and a new solution is proposed which uses cryptographic authentication for the broadcasted images The proposed application is implemented in Java and can run on any device from standard computers to mobile phones Also some experimental results are presented for the case when a mobile phone is used as a receiver this case being relevant as the device is the potential receiver with the most constrained computational resources Keywords video surveillance availlability accessibility authenticity I INTRODUCTION Video surveillance has a number of benefits that are indispensable for today s society it helps
9. alues are digitally signed by the VCM C Experimental results In tables 3 and 4 some communication statistics in the context of a mobile phone used as a receiver are presented the squaring function was used for the construction of the chain The mobile phone is the device with the lowest computational power that we have and most of the limitations on the number of packets that can be sent per second come from the speed of the Internet connection offered on mobile phones by Orange Mobile Operator 15 Experimental results show that 2 to 4 frames per seconds are feasible to receive on the Nokia 6288 mobile phone implementation was done on the Nokia Series 40 SDK 12 Even if this is not a real time transmission which requires in the order of tens of frames per second we believe that this is a sufficient frame rate for a home video surveillance task carried on a mobile phone More this frame rate is available on a mobile phone that has low computational power and the main limitation is from the network speed Of course the frame rate will get to real time if a standard computer is used as a receiver We also note that in the applications it is better for the keys and MAC to be received on different threads than the images since the images may be checked for authenticity even if they arrive lately as long as the key and MAC is in the correct time interval Also to save up computational time on the remote device in the registration stage t
10. armful as they are in separate time intervals of several seconds each which have almost no meaning for the video surveillance system Now we get to the second kind of cause for system unavailability which comes from communications failures Here our only concern is that the communication protocol itself can be subject to DoS attacks Of course if the network resources are exhausted by legitimate users then the network must be properly re designed In the context of protocol failures DoS protection techniques possibly the use of cryptographic puzzles should be considered in the design of the protocol In brief precautions should be taken both on the sender and on the receiver side On the sender side the biggest concern is computational power therefore simple cryptographic primitives such as hash functions and MAC codes should be used we will follow this in our application On the receiver side the concern is both on the computational power and communication bandwidth as it is expected to have receivers with different communication abilities For this purpose it is desirable for the protocol to allow different frame rates for different receivers our application will respond to this requirement as well As a partial conclusion we consider that availability can be easily reached by following good engineering practices Equipment reliability should not represent a problem as it is not difficult to achieve but at most expensive with parallel
11. e is no redundant source of power all cameras will fail Such a failure caused by a common element on which all other elements of the system depend is called common mode failure Further this kind of failure can have a variety of more subtle causes from incorrect design of products by the same manufacturer to incorrect installation by the same individual Thus for a given system one should compute the availability for the entire system using well known rules and some experimental data and add more redundancy if the availability level is not sufficient any basic book on the subject can be consulted 1 Four nines availability means that the system is available for 99 99 percents of the time this still gives 52 6 minutes of unavailability per year On a first view such an amount of time can be enough to exploit a system Therefore 5 nines which means 99 999 percents up time or higher availability levels should be achieved However this intuition is not necessarily correct as availability 1s not a measure for the duration of a particular system failure We used as example data records from May 2008 on the power failures at the aut upt ro server at our university Due to several work outs on the energy supply infrastructure 19 power failures were recorded However these power failures were due to energy fluctuations and they last in the order of seconds Although their sum could give less than 5 nines availability still they are not h
12. erver side as long as the communication protocol matches However there is not a large set of choices for the implementation of the client side which will run on low power devices as well For example when we are working on mobile phones Java may be the only alternative As a partial conclusion for accessibility considerations we can state that the computational requirements must be kept at the level of simple cryptographic operations such as hash functions and MAC codes while the implementation must be done in an environment that is independent on the computer architecture such as Java TABLE I COMPUTATIONAL TIME FOR SOME CRYPTOGRAPHIC PRIMITIVES IN NET C 1024 Bit 1024 Bit SHA256 aaa Modular Modular Bouncy framework Multiplication Exponentiation Bouncy Bouncy 3 1x10 s 1 87x10 s 371 x10 s 33 43 x10 s 6 TABLE II COMPUTATIONAL TIME FOR SOME CRYPTOGRAPHIC PRIMITIVES IN JAVA BOUNCY USED ON THE MOBILE PHONE 5 HMAC Lea Bit 1024 Bit Modular SHA230 SHA256 peouulak Exponentiation Multiplication P 2 ar eas eee eae 6 6 54 x10 s 11 1 x10 s 96 9 x10 s 41 5 xl0 s 3 3 3 1 2 5 B Availability For a surveillance system availability is twofold as there are two distinct causes of unavailability First 1t is equipment reliability it may be expected that equipments fail thus making the service unavailable However note that equipment availability is a necessary condition but
13. he last disclosed key signed by the sender is given Otherwise if a receiver has a key which was disclosed he will need to compute A tey tsari 5 tes until he will synchronize with the current key of the sender TABLE III COMMUNICATION STATISTICS AT 320X240 RESOLUTION Key disclosure Packets Authentic packets Loss rate A Geconds sent received ae TABLE IV COMMUNICATION STATISTICS AT 160X120 RESOLUTION D Performance analysis An analysis of the performance of the protocol with respect to the frame rate is useful In order to correctly display a frame one will need to receive a packet and verify the key and the MAC code this gives f frame ae ae T a a ler MAC 1 Now because of the time synchronization issues in the case when each frame is sent in a distinct packet we must have O gt t rame 2 If 2 does not hold then the received frame will fail the authenticity test as it will be received to late outside the correct time interval for the corresponding key This relation actually gives the limitation on the frame rate for the case when each frame is authenticated with a distinct key Therefore the maximum achievable frame rate in this case will be l MAX 5 ome rate t 3 frame However this will impose the use of a transfer rate that is established by the receiver with the worst bandwidth and this may not be fair with respect to other receivers For this purpose we allow each receiver
14. n the computational time for hash functions and for digital signature can be done In brief synchronization requires the same amount of time as authenticating hundreds of messages The cleanest solution that can be used is to use a distinct time server than the VCM as stated previously Another solution will be to provide time synchronization only to legitimate users that authenticate to the VCM and only after certain periods of time as it is unlikely for users to lose synchronization too quickly A detailed analysis for DoS attacks on the TESLA protocol is available in 7 we consider as potential future work to use several suggested improvements gt Authenticity The protocol guarantees the authenticity of the information by the use of MAC codes and time synchronization Two constructive techniques can be employed for the key chain the use of hash functions and the use of modular multiplication whose computational time is close to the range of a hash functions In the later case the security of the protocol is provable to be equivalent to the integer factorization problem which is infeasible to solve Z Surveillance Area Untrusted Server Wide Area Network Figure 2 Application setting for the proposed system B Protocol description In our application we have also used the function f x x modn instead of a hash function for the construction of the chain this is a significant difference from
15. not a sufficient one as equipments may be up and working while the communication may be halted due to some computational or communication overload Therefore we distinguish between equipment availability and protocol availability Regarding equipment availability which is closely related to equipment reliability there were attempts to discus it in the context of video surveillance systems 9 However there are no particular details or experimental data in 9 that are specific for a surveillance system and only the general availability theory is stated Here we will briefly state in a few lines what we consider that is relevant to be taken into account in the context of a surveillance system In general the availability of a system can be characterized as the ratio between the up time and the T sum of the up time and down time i e 4 _ ie I down Further unavailability is U 1 A Obviously if one wants to increase availability it can simply use parallel redundancy i e more devices performing the same function For parallel systems unavailability is the product of the components n unavailability ic U U and since U lt 1 Vi 1 n i l the unavailability of the parallel system drastically decreases However what needs to be added is that in any system there may still be single elements that can cause the failure of the entire system For example consider a power down case in this case if ther
16. not be shared since if two users know the same secret key they can impersonate each other to the system etc Further using distinct keys for each user implies computing different cryptographic operations as well thus degrading performance Therefore the discussion that follows and the system that is proposed are mainly oriented on the AAA framework We note that the notion of AAA framework is also used in different contexts with different significance for the three A s To the best of our knowledge the AAA framework with the significance from this paper is new and it is not our intention to overlap with well established terminology but this abbreviation follows straight forward from the desired security objectives of our system Of course there are also other aspects of video surveillance such as pattern recognition motion detection and tracking etc 2 Here we are not concerned with such objectives as we are mainly focused on the security of the transmission Also for a complete view on closed circuit television CCTV surveillance a basic book on the subject can be consulted 4 A survey on encryption techniques used for multimedia contents is available in 5 The paper is organized as follows Section 2 is a discussion along the AAA framework accessibility availability and authenticity In section 3 we take a brief account on the DCS 900 IP camera while in section 4 we describe the system that we propose as a valid response unde
17. partially supported by national research grant PNCDI PN H 940 2009 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 REFERENCES J P Bentley An Introduction to Reliability and Quality Engineering Addison Wesley ISBN 0201331322 216 pages 1998 R Collins A Lipton T Kanade H Fujiyoshi D Duggins Y Tsin D Tolliver N Enomoto O Hasegawa A System for Video Surveillance and Monitoring tech report CMU RI TR 00 12 Carnegie Mellon University May 2000 B Groza D Pop I Silea Java Implementation of an Authentication Protocol with Application on Mobile Phones IJEEE TTTC International Conference on Automation Quality amp Testing Robotics AQTR 2008 THETA 16 H Kruegle CCTV Surveillance Analog and Digital Video Practices And Technology Elsevier ISBN 13 978 0 7506 7768 4 ISBN 10 0 7506 7768 6 656 pages 2006 X Liu A Eskicioglu Selective Encryption of Multimedia Content in Distributed Networks Challenges and New Directions IASTED Communications Internet amp Information Technology CIIT November 2003 A Perrig R Canetti J D Tygar D Song The TESLA Broadcast Au thentication Protocol In CryptoBytes 5 2 Summer Fall pp 2 13 2002 A Perrig R Canetti D Song D Tygar Efficient and Secure Source Authentication for Multicast Proceedings of Network and Distributed System Security S
18. r the AAA framework Section 5 holds the conclusions of our paper II DEALING WITH ACCESSIBILITY AVAILABILITY AND AUTHENTICITY A Accessibility As accessibility tends to focus on people with disabilities and their right to access public services we can increase our word power and use this term with focus on computational devices which can have a large spectrum of technical specifications For example remote devices can include laptop computers PDAs mobile phones etc and certainly there are major differences between them from the hardware e g memory CPU up to the software e g operating system An accessible service should be usable from any such device Therefore accessibility is not itself a security objective however more important it is a desired characteristic for any service provided by some system The security implications of this objective are that as computational power tends to be very different on distinct devices making a service accessible by different kinds of devices imposes certain security restrictions In tables 1 and 2 we synthesize some experimental results that we get on the computational time required by some devices to compute several cryptographic primitives time was taken as the mean of several hundreds to thousands runs of the corresponding cryptographic primitive We used processors with different capabilities from Intel Core 2 to Intel PXA for mobile devices and ARM processors for mobile phones
19. rs of the password used in the setup wizard then it will work which proves that the password is actually truncated by the setup wizard to the first 8 characters gt Password disclosure vulnerabilities In the default settings with the user access control option disabled we captured packets in which the admin id and password are sent in clear text Although it is highly recommended in the user manual to change admin password to a stronger password by default it is set to blank by analyzing network traffic with Wireshark we seen that the password itself is sent in clear text on the communication line and therefore can be extracted by any adversary that can analyze network traffic It is not clear for us why this happens only when the access control option is disabled as the camera software is not open source but an adversary that eavesdrops on the communication line in the initial setup stage when the user access control option is disabled can certainly capture the password One such adversary may be an ISP provider or any administrator from the network nodes over which your network traffic is routed Capturing the admin password is a serious threat as one can subsequently do anything from making the camera inaccessible to increasing the delay at which the pictures are taken even changing the IP of the camera or installing a dummy camera on the same IP The scenario in which we tested is depicted in figure 1 Wireshark was running on the
20. the 5 66 78 18 order of micro seconds the computational time for the cryptographic primitives will not affect the frame rate Also the size of the key is not significant compared to the size of the packet which is determined mostly by the size of the image Usually the image has several kilo bytes while the size of the key will be at most several thousand bits if the squaring function is used sh Chains 5fpk_ QR Chains 5fbk Yt z EATA e p pe gL P P 2 Hash Chains Lfpk QR Chains Lfpk 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ll 1 20000 40000 60000 80000 100000 120000 Figure 3 Frame rate variations with network speed of 128kbps for an average 10kb frame V CONCLUSIONS A framework of three properties of a surveillance system was depicted availability accessibility authenticity AAA The DCS 900 camera an off the shelf device was analyzed and its weaknesses shown Also an improved solution was proposed which responds to the necessities of the AAA framework The experimental results show that frames can be received even by a mobile phone with low computational power The proposed solution is still under development and its complete specifications remain as future work for us We used the DCS 900 camera just as an intuitive example however a comparison between several surveillance cameras in the context of the introduced framework is a potential interesting future work Acknowledgements This work was
21. to choose its own frame rate We underline that this can be further improved if more than one frame are authenticated with the same key thus reducing the time for the verification of a key and MAC in relation 1 This will lead to the following Lies e t t te Key 4 verMAC 4 frame receive n n However in this situation each receiver will need a buffer to store n frames until the authentication key will arrive Also the delay until the received frame can be actually proved to be authentic is larger Thus now we can establish the frame rate based on the network speed and the time to compute the cryptographic primitives In the plot from figure 3 we depict the theoretical frame rate for both hash chains and quadratic residues chains As can be easily seen in figure 3 the frame rate cannot get to higher than 10 fps mainly because of communication bandwidth in this plot we have assumed 128 kbps which is a suggested value for 3G networks in moving Key disclosure Packets Authentic packets Loss rate a Geconds E e MEE AG 0175 O 15 O vehicles however on the Internet connection used for the results in tables 2 and 3 the bandwidth was even worst than this In figure 3 we also indicate the frame rate for the case when more then 1 frame is inside a packet 5 fpk denotes that there are 5 frames in a packet 1 e 5 frames per key We note that on standard computers as modular multiplications and hash functions can be computed in
22. to prevent theft and vandalism of public and private places prevent violence and crime protect children and even improve customer image and trust on a particular vendor A website dedicated to all aspects regarding video surveillance is available at 16 In the last decade video surveillance has evolved from analog transmission over coaxial cables to digital transmission over the Internet In this context video surveillance raises new challenges and especially from a security perspective Nowadays any end user can buy almost inexpensive surveillance devices from the market in order to assure the security of his home and business However the question that remains is how secured are such off the shelf devices Security can be characterized by a simple equation the existence of vulnerabilities and adversaries implies the existence of security risks So the first question that needs to be answered is what adversaries may have malicious interests on a system It is no doubt that adversaries may vary from robbers to hackers However it is quite obvious that combinations between multiple kinds of adversaries and not a single stand alone adversary are the most dangerous So an IP camera such as the DCS 900 camera that we used as a practical example in one of the following sections can certainly protect users up to some extent against burglars But if burglars associate with hackers does the camera offer protection as well Since we have
23. two adversaries in the extent of the aforementioned security equation if we also have vulnerabilities with respect to either of the adversaries then we have a security risk So the question is what vulnerabilities do IP cameras which transmit information over the Internet hide Before answering to this question let us first depict three characteristics that an efficient trustworthy video surveillance system must have a Accessibility the system must be accessible by remote devices with different computational resources and communication bandwidth b Availability the system must respond positive when a particular service is requested c Authenticity the information that is sent by the system must be authentic this implies both a secure timeline and a guarantee over the source of the information We can also add to these two more objectives that are needed for the privacy of the video surveillance system c access control the system must be accessible and configurable only by users that have the corresponding rights and d confidentiality the information from the system cannot be accessed by illegitimate users Indeed legal implications with respect to privacy may arise in practice and these two last objectives may be relevant in some contexts but more important they may be irrelevant as long as the first three objectives are not assured Also assuring privacy objectives implies the use of secret keys that can
24. ymposium 2001 A Perrig R Canetti J D Tygar D Song Efficient Authentication and Signing of Multicast Streams Over Lossy Channels IEEE Symposium on Security and Privacy 2000 S Sutor F Matusek F Kruse K Kraus R Reda Large Scale Video Surveillance Systems New Performance Parameters and Metrics The Third International Conference on Internet Monitoring and Protection 2008 Bouncycastle org Bouncy Castle Crypto API http www bouncycastle org latest_releases html D Link Building Networks for People http www dlink com Forum Nokia Series 40 Platform 3rd Edition SDK http www forum nokia com info sw nokia com id cc48f9al fScf 447b bdba c4d41b3d05ce Series 40 Platform SDKs html Java Sun Java 2 http java sun com javame index jsp MIL HDBK 217F Reliability Prediction of Electronic Equipment 1995 availlable at http assist daps dla mil quicksearch basic_profile cfm ident_ number 53939 Micro Edition Orange Mobile Operator Mobile Internet Access http www orange ro abonamente date mobile internet html Video surveillance security for your World http www videosurveillance com
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