Group membership service for intrusion tolerance

Intrusion tolerance is the capability of internet systems which withstand attacks and intrusions under unsafe environment. Its precondition is redundancy and replication of information. This paper presents the architecture of an intrusion tolerant system and group communication technology has been introduced because of information replication characteristic. Group membership service is one of the most important constitutes of group communication. The paper describes group membership algorithm and termination condition of the algorithm in detail. Blocking detection and avoidance are also depicted. Group membership service has been extended from LAN to WAN environment. Finally, we have developed a group membership prototype system on WAN condition. Experiment results show that the algorithm has a well performance even though running in complicated Internet.