Optimal Unconditionally Secure ID-Based Key Distribution Scheme for Large-Scaled Networks ∗
Goichiro Hanaoka, Tsuyoshi Nishioka, Yuliang Zheng, Hideki Imai · IEICE Transactions on Fundamentals of Electronics Communications and Computer Sciences · 2001
SUMMARY Efficient ID-based key sharing schemes are desired worldwide in order to obtain secure communications on the Internet and other related networks, and Key Pre-distribution System (KPS) is one ofthe majority ofsuch key sharing schemes. The remarkable property ofKPS, is that, user need only input the partner’s identifier to the secret KPS-algorithm in order to share a key between them. Although this is just a small part of many advantages KPS has in terms ofefficiency, an enormous amount ofmemory is always required to achieve perf ect security. While the conventional KPS methods can establish communication links between any pair ofentities in a communication system, in most ofthe practical communication environment, such as in a broadcast system, not all links will be required. In this article, we achieved a desirable method to remove the unnecessary communication links between any pair ofentities in a communication system. In our scheme, required memory size per entity was just proportional to the number ofentities ofthe partner’s, while that in conventional KPS, it is proportional to the number ofentities ofthe whole communication system. As an example, ifan entity communicates with only 1/r others, the memory requirement is reduced to 1/r ofthe conventional KPS’s. Furthermore, it was proven that the obtained memory size was optimum. Overall, our scheme confirmed greater efficiency to achieve secure communication particularly suited in large-scale networks.