Distributed or parallel rule-based systems are currently needed for real applications. The proposed architecture of such a system is based on a wrapper allowing the cooperation between several instances of the rule-based system running on different computers of a cluster. As case study a parallel version of the Java Expert System Shell is built. Initial tests show its efficiency when running classical benchmarks. Moreover, this parallel version of Jess is successfully used to accelerate current simulators for membrane computing. Key words. Rule-based system, cluster computing, membrane computing