PROM: A support for robust replication in a distributed object environment

The concept of object can be employed to achieve tolerance to hardware faults in distributed systems. Replication by introducing several copies for each object allows a continuous service even in case of failure. In particular, the paper describes an object model, PROM, which exploits replication by defining several passive back-up copies for any object. The system automatically recovers any failure of a copy in execution by activating a spare copy and restarting it from a previous checkpoint. The aim of the paper is the analysis of the effective support for PROM. This support is organized in structured levels on a distributed architecture. The services that the support should include to guarantee the desired replication model are described. © 1990, Science Press, Beijing China and Allerton Press Inc.. All rights reserved