Increasing the robustness of initial key agreement using failure detectors

This paper considers the problem of fault-tolerance and built-in robustness in key agreement for dynamic peer groups. A fault-tolerant key establishment protocol is developed by extending the group Diffie-Hellman key agreement protocol to support asynchronous settings and faulty participants. The protocol uses recent results on failure detection in asynchronous distributed systems. Simulation results show that the key agreement protocol augmented with failure detection increases significantly the number of group members that participate in the computation of the group key while introducing a low message overhead.