C. Nita-Rotaru, Y. Amir, Y. Kim, J. Schultz, J. Stanton, and G.Tsudik

CERIAS TR 2004-58

article

Contributory group key agreement protocols generate group keys based on contributions of all group members. Particularly appropriate for relatively small collaborative peer groups, these protocols are resilient to many types of attacks. Unlike most group key distribution protocols, contributory group key agreement protocols offer strong security properties, such as key independence and perfect forward secrecy. This paper presents the first robust contributory key agreement protocol resilient to any sequence of group changes. The protocol, based on the Group Diffie-Hellman contributory key agreement, uses the services of a group communication system supporting Virtual Synchrony semantics. We prove that it provides both Virtual Synchrony and the security properties of Group Diffie-Hellman, in the presence of any sequence of (potentially cascading) node failures, recoveries, network partitions and heals. We implemented a secure group communication service, Secure Spread, based on our robust key agreement protocol and Spread group communication system. To illustrate its practicality, we compare the costs of establishing a secure group with the proposed protocol and a protocol based on centralized

PDF

2004 – 05

IEEE Transactions on Parallel and Distributed Systems (TPDS)

Nita-Rotaru

5

468-480

15

2004-05-01

1 Introduction 2 Failure Model and Security Assumptions 3 Problem Definition 4 Basic Robust Algorithm 5 An Optimized Robust Algorithm 6 Implementation 7 Performance Evaluation 8 Related Work 9 Conclusions

English

A hard-copy of this is in the CERIAS Library

Secure Group Communication Using Robust Contributory Key