MIME-Version: 1.0 Server: CERN/3.0 Date: Sunday, 24-Nov-96 22:05:18 GMT Content-Type: text/html Content-Length: 1826 Last-Modified: Saturday, 17-Feb-96 00:50:09 GMT Unreliable Failure Detectors for Reliable Distributed Systems

Unreliable Failure Detectors for Reliable Distributed Systems

by Tushar Deepak Chandra and Sam Toueg. This paper has 51 pages. To get a postscript copy of this paper, click here (or here to get it from the mirror site). To appear in JACM.

Abstract

We introduce the concept of unreliable failure detectors and study how they can be used to solve Consensus in asynchronous systems with crash failures. We characterise unreliable failure detectors in terms of two properties --- completeness and accuracy. We show that Consensus can be solved even with unreliable failure detectors that make an infinite number of mistakes, and determine which ones can be used to solve Consensus despite any number of crashes, and which ones require a majority of correct processes. We prove that Consensus and Atomic Broadcast are reducible to each other in asynchronous systems with crash failures; thus the above results also apply to Atomic Broadcast. A companion paper shows that one of the failure detectors introduced here is the weakest failure detector for solving Consensus [CHT92].
Research supported by an IBM graduate fellowship, NSF grants CCR-8901780 and CCR-9102231, DARPA/NASA Ames Grant NAG-2-593, and in part by Grants from IBM and Siemens Corp.
Maintained by tushar@watson.ibm.com