To address issues of availability and security, distributed services must rely on mechanisms for maintaining consistent intermediate state and for making coordinated decisions. Implementing reliable multicast in an insecure environment with arbitrary failures incurs inevitable overhead required for maintaining 16 consistency. The Rampart toolkit for building high-integrity services . Note that we do not aim to tolerate Byzantine faults, value faults in the gateway, or faults in the group communication system itself. Object factories are used to kill and start replicated applications, depending on decisions made by the dependability manager, and to provide information regarding the host to the dependability manager.
Gateways provide two functions.
99-110, SpringerVerlag, 1995. The Rampart toolkit for building high-integrity services . In Theory and Practice in Distributed Systems, volume 938 of Lecture Notes in Computer Science, pages 99-110, Berlin, 1995. Group communication protocols support a group of the processes with the reliable and ordered delivery of messages to multiple destinations. The group communication protocols discussed so far assume that every pair of processes support the same and fixed delay time and the same level of reliability.