A case for a multi-key secure video proxy: theory, design, and implementation

ABSTRACT

Because of limited server and network capacities in multimedia streaming, proxies are commonly used to cache multimedia objects such that, by accessing nearby proxies, clients can enjoy smaller start-up latencies and reduced packet loss and delay jitters for their requests. However, the use of video proxies increases the risk that multimedia data are exposed to unauthorized access by intruders. In this paper, we present a framework for implementing a secure video proxy or, more generally, a secure proxy architecture. The framework employs a notion of asymmetric reversible parametric sequences to provide the following security properties: (1) data confidentiality during transmission, (2) end-to-end data confidentiality, (3) data confidentiality against proxy intruders, and (4) data confidentiality against member collusion. Our framework is grounded on a multi-key RSA technique such that system resilience against attacks is provably strong given standard computability assumptions. We also propose the use of a set of encryption configuration parameters to trade off proxy encryption throughput against the viewing quality of video by unauthorized parties. Implementation results on a Pentium III/800 MHz machine show that our techniques can simultaneously achieve high encryption throughput and extremely low video quality (in terms of both PSNR and the visual quality of decoded frames) during unauthorized viewing.

REFERENCES

• 1: Carsten Griwodz , Oliver Merkel , Jana Dittmann , Ralf Steinmetz, Protecting VoD the easier way, Proceedings of the sixth ACM international conference on Multimedia, p.21-28, September 13-16, 1998, Bristol, United Kingdom [doi>10.1145/290747.290751]
• 2: Stephane Gruber , Jennifer Rexford , Andrea Basso, Protocol considerations for a prefix-caching proxy for multimedia streams, Proceedings of the 9th international World Wide Web conference on Computer networks : the international journal of computer and telecommunications netowrking, p.657-668, June 2000, Amsterdam, The Netherlands
• 3: Y. Guo, S. Sen, and D. Towsley. Prefix caching assisted periodic broadcast: Framework and techniques to support streaming for popular videos. In IEEE ICC, 2002.
• 4: J. Kangasharju, F. Hartanto, M. Reisslein, and K. W. Ross. Distributing layered encoded video through caches. In Proceedings of IEEE Infocom 2001, pages 1791--1800, Anchorage, Alaska, April 2001.
• 5: Refik Molva , Alain Pannetrat, Scalable multicast security in dynamic groups, Proceedings of the 6th ACM conference on Computer and communications security, p.101-112, November 01-04, 1999, Kent Ridge Digital Labs, Singapore [doi>10.1145/319709.319723]
• 6: R. Rejaie, M. Handley, H. Yu, and D. Estrin. Proxy caching mechanism for multimedia playback streams in the internet. In Proceedings of the 4th International Web Caching Workshop, San Diego, CA., March 1999.
• 7: B. Schneier. Applied Cryptography. John Wiley and Sons, New York, 1996.
• 8: S. Sen and D. Towsley. Proxy prefix caching for multimedia streams. In IEEE INFOCOM, New York, March 1999.
• 9: Changgui Shi , Bharat Bhargava, A fast MPEG video encryption algorithm, Proceedings of the sixth ACM international conference on Multimedia, p.81-88, September 13-16, 1998, Bristol, United Kingdom [doi>10.1145/290747.290758]
• 10: A. S. Tosun and W. chi Feng. Secure video transmission using proxies. In Technical Report, Computer and Information Science, Ohio State Univeristy, 2002.
• 11: S. F. Yeung, J. C. S. Lui, and D. K. Y. Yau. A case for a multi-key secure video proxy: Theory, design, and implementation. Technical report, Dept of Computer Science and Engineering, Chinese University of Hong Kong, Hong Kong, 2002. Also as CS TR-02--011, Purdue University, West Lafayette, IN.

INDEX TERMS

Keywords:
asymmetric parametric sequence functions, multi-key RSA, security, video proxy