Service replication in Grids: Ensuring consistency in a dynamic, failure-prone environment

Abstract

A major challenge in a service-oriented environment as a Grid is fault tolerance. The more resources and services involved, the more complicated and error-prone becomes the system. Migol (Luckow and Schnor, 2008) is a Grid middleware, which addresses the fault tolerance of Grid applications and services. Migol's core component is its registry service called application information service (AIS). To achieve fault tolerance and high availability the AIS is replicated on different sites. Since a registry is a stateful Web service, the replication of the AIS is no trivial task. In this paper, we present our concept for active replication of Grid services. Migol's Replication Service uses a token-based algorithm and certificate-based security to provide secure group communication. Further, we show in different experiments that active replication in a real Grid environment is feasible.