Securing RTP Packets Using Per-Packet Selective Encryption Scheme for Real-Time Multimedia Applications

To secure multimedia communications, existing encryption techniques usually encrypt the whole data stream using the same session key during a session period. The use of online session key usually confronts with tradeoff problem between latency caused when session key is created and security strengths for the real-time multimedia stream. In this paper, we propose a selective packet key encryption scheme that selectively encrypts RTP packets using different keys in the same session for real-time multimedia applications. Our proposed scheme has two important features. First, a one-time packet key, which was already been used, will never be reused throughout a session. This feature improves security strength of real-time multimedia. Second, each packet is selectively encrypted. This contributes to reduce the average latency caused by one-time packet key exchange.