New Fault Tolerance Approach using Antecedence Graphs in Multi Agent Systems

Abstract: Mobile agents are distributed programs which can move autonomously in a network, to perform tasks on behalf of user. They are susceptible to failures due to faults in communication channels, processors or malicious programs. In order to gain solid foundation at the heart of today’s e-society, the mobile agent technology must address the issue of fault tolerance. Checkpointing has been widely used technique for providing fault tolerance in mobile agent systems. But the traditional message passing based checkpointing and rollback algorithms suffer from problems of excess bandwidth consumption and large overheads. This paper proposes use of antecedence graphs and message logs for maintaining fault tolerance information of agents. For checkpointing, dependent agents are marked out using antecedence graphs; and only these agents are involved in process of taking checkpoints. In case of failures, the antecedence graphs and message logs are regenerated for recovery and then normal operation continued. The proposed scheme reports less overheads, speedy execution and reduced recovery times as compared to existing graph based schemes