It is challenging to provide authentication to time-critical multicast data, where low end-to-end delay is of crucial importance. Consequently, it requires not only efficient authentication algorithms to minimize computational cost, but also avoidance of buffering packets so that the data can be immediately processed once presented. Desirable properties for a multicast authentication scheme also include small communication overhead, tolerance to packet loss, and resistance against malicious attacks. In this paper, we propose a novel signature model - Time Valid One-Time Signature (TV-OTS) - to boost the efficiency of regular one-time signature schemes. Based on the TV-OTS model, we design an efficient multicast authentication scheme "TV-HORS" to meet the above needs. TV-HORS combines one-way hash chains with TV-OTS to avoid frequent public key distribution. It provides fast signing/verification and buffering-free data processing, which make it one of the fastest multicast authentication schemes to date in terms of end-to-end computational latency (on the order of microseconds). In addition, TV-HORS has perfect tolerance to packet loss and strong robustness against malicious attacks. The communication overhead of TV-HORS is much smaller than regular OTS schemes, and even smaller than RSA signature. The only drawback of TV-HORS is a relatively large public key of size 8KB to 10KB, depending on parameters.
Qiyan Wang is a Ph.D candidate in the Department of Computer Science, University of Illinois at Urbana-Champaign. He is interested in applied cryptography for communication security, especially in key management and multicast authentication. He got his Bachelor's degree on Information Security in 2007 from the University of Science and Technology of China.