A NEW PROBABILISTIC REKEYING METHOD FOR SECURE DYNAMIC GROUPS

摘要

Logical Key Hierarchy (LKH) is a basic method in secure multicast group rekeying. LKHmaintains a balanced tree which provide uniform cost of O(log N) for compromise recovery, where N is group size. However, it does not distinguish the behavior of group members even though they have different probabilities of join or leave. When members have diverse changing probability the gap between LKH and the optimal rekeying algorithm will become bigger. The Probabilistic optimization of LKH (PLKH) scheme, optimized rekey cost by organizing LKH tree with user rekey characteristic. In this paper, we concentrate on further reducing the rekey cost by organizing LKH tree with respect to compromise probabilities of members using new join and leave operations. Simulation results show that our scheme performs 18% to 29% better than PLKH and 32% to 41% better than LKH.