Wiring constraints often result in a trade-off between efficiency and realizability when designing communication networks for multicomputers. By combining the connectivity of multistage networks with the easy to realize mesh networks, the Mesh of Clos topology tries to narrow this gap. In this paper, a simulation study is presented in order to evaluate wormhole routed Mesh of Clos communication networks. It is shown that this type of network can substantially reduce contention as compared to flat mesh networks. Furthermore, we found that increasing the number of flitbuffers on router devices does not necessarily lead to improvedcommunication performance. For some application loads it may even result in a loss of performance. 1 Introduction Distributed memory MIMD multicomputers play an important role in the ever continuing pursuit of improving computational power. Usually these multicomputers are constructed by a network of nodes, where each node consists of a processor, local memory ..