Minimization of rekeying cost for contributory group communications

Document Type

Conference Proceeding

Date of Original Version



While contributory group key agreement is a promising solution to achieve access control in collaborative and dynamic group applications, the existing schemes have not achieved the performance lower bound in terms of rekeying overhead. In this paper we introduce a contributory group key agreement that achieves the performance lower bound by utilizing a novel logical key tree structure, called PFMH, and the concept of phantom user position. In particular, the proposed scheme only needs O(1) rounds of two-party Diffle-Hellman upon any single user join event and O(log n) rounds of two-party Diffle-Hellman upon any single user leave event. Both theoretical bound analysis and simulation studies show that the proposed scheme achieves much lower rekeying cost than the existing tree-based contributory group key agreement schemes. © 2005 IEEE.

Publication Title

GLOBECOM - IEEE Global Telecommunications Conference