Improvement of Temporal-Replication Mechanism in Mobile Agent System Fault-Tolerant Model

Fault-tolerant is one of the most important content of mobile-agent system. After studying the existing mobile-agent system fault-tolerant mechanisms both in domestic and overseas, this paper is concerned with temporal-replication methodology. On the basis of witness agent approach, which was proposed by Michael R.Lyu etc, in this paper a progressed mechanism was introduced. There are two aspects of improvement, the one is to keep address and timestamp of the nodes that agent has traveled; the other is to employ the agent creation node as a fixed backup. This approach can handle server failures, place failures, and failures in message passing. It is capable of detecting and recovering most failure scenarios in mobile agent systems. We describe the design of our fault-tolerant approach to mobile agent systems, and conduct reliability evaluation for our approach by using simulation tools of C-Sim and Matlab. The evaluation results show our approach is a promising technique in achieving mobile agent system reliability.