Current research activities on the problem of key management in group communicauon system include towareas : one to solve the problem of key updating and distribution in large dynamic multicast groups; another to solvethe problem of key agreement in the DPGs(dynamic peer groups). The two research areas are independent with eachother. In this paper, we show a new research direction, under which we can effectively combine the correspondingtechniques in these two fields to solve new problems, and also give a good demonstration that through combining theGDH techniques of key agreement m DPGs and our techniques of key management in large dynamic multicast groups,we present a robust and fault-tolerant key management protocol suite in large dynamic multicast group. The protocolsuite solve the problem of SPOF(single point of failure)which universally exists in center-oriented key managementprotocols and is robust and fault-tolerant.
