Agreementon the membership of a group of processes in a distributed system is a basic problem that arises in a wide range of applications. Such groups occur when a set of processes co-operate to perform some task, share memory, monitor one another, subdivide a computation, and so forth. In this paper we discuss the Group Membership Problem as it relates to failure detection in asynchronous, distributed systems. We present a rigorous, formal specification for group membership under this interpretation. We then present a solution for this problem that improves upon previous work.

No abstract

No abstract

No abstract

Failure detectors (or, more accurately Failure Suspectors -FS) appear to be a fundamental service upon whach to buald fault-tolerant, distributed applacataons. This paper shows that a FS with very weak semantics (i.e. that delivers failure and recovery information in no specific order) suffices to implement virtually-synchronous communication (VSC) in an asynchronous system subject to process crash failures and network partitions. The VSC paradigm is particularly useful in asynchronous systems and greatly simplifies building fault-tolerant applications that mask failures b y replicating processes. We suggest a three-component architecture to implement virtuallysynchronous communication : 1) at the lowest level, the FS component; on top of at, 2a) a component that defines new views, and 2b) a component that reliably multicasts messages within a view.