A Dynamic Fault Tolerant Algorithm Based on Active Replication

To the wide area network oriented distributed computing such as Web services, a slow service is equivalent to an unavailable service. It makes demands of effectively improving the performance without damaging availability to the replication algorithms. Aim for improving the performance of the active replication algorithm, we propose a new replication algorithm named AAR (Adaptive Active Replication). Its basic idea is: all replicas receive requests, but only the fastest one returns the response. Its main advantages are: (1) The response is returned by the fastest replica; (2) The algorithm is based on the active replication algorithm, but it avoids the redundant nested invocation problem. We prove the advantages by analyzing and experiments.