improving fault-tolerance by replicating agents
Despite the considerable efforts spent on developing multi-agent systems the actual number of deployed systems is surprisingly small. One of the reasons for the significant gap between developed and deployed systems is their brittleness.The absence of centralized control components makes it difficult to detect and treat failures of individual agents thus risking fault-propagation that can seriously impact the performance of the system. Using redundancy by replication of individual agents within a multi-agent system is one possible approach for improving fault-tolerance. Unfortunately the introduction of replicates leads to increased complexity and system load. In this paper we examine the use of transparent agent replication, a technique in which the replicates of agents appear and act as one entity thus avoiding an increase in system complexity and minimizing additional system loads. The paper defines transparent agent replication and identifies the key challenges in using it. Special attention is given to the inter-agent communication, read/write consistency, resource locking, resource synthesis and state synchronization. An implementation of the transparent agent replication for the FIPA-OS framework is presented and the results of testing it within a real-world multi-agent system are shown.
fault-tolerance replicating agents fipa-os