Mobile Agents for Information Retrieval: Detection and Recovery From Failures.

Mobile agent is a distributed program which can move autonomously in a network, to perform its tasks, on behalf of the user. During migration, the mobile agents and so its data are susceptible to failures due to the faults in the network components like the machine and the channel. It is a challenging issue to address the mobile agent failure scenario during its migration. This paper presents a failure recovery model for mobile agents that ensure the recovery of the lost mobile agent and the data. This is done by allowing a replication of the actual mobile agent at the previously visited servers. However, unlike existing methods, in this paper the replication is temporary and limited to an optimal value. This is achieved by making the mobile agents that operates in multi-region environment, to track, communicate and share the retrieved information between them. After the information sharing, in this paper, the number of replica to be maintained at each region is reduced to one. Furthermore, as there is at least one server in each region that holds the replica, this paper guarantees that the information collected at each server is not lost. In addition, the presented model survives the region failure too, when implemented in a multi-region environment. Experiments were conducted in a web environment, and the results obtained are analyzed and compared with existing methods, based on different testing parameters. The experimental results appear to be more encouraging in claiming the presented recovery model to be a reliable one. [ABSTRACT FROM AUTHOR]