In this paper, we present a performance evaluation of a wide-area cluster system based on a rewallenabled Globus metacomputing toolkit. In order to establish communication links beyond the rewall, we have designed and implemented a resource manager called RMF (Resource Manager beyond the Firewall) and the Nexus Proxy, which relays TCP communication links beyond the rewall. In order to extend the Globus Metacomputing Toolkit to the rewall-enabled toolkit, we have built the Nexus Proxy into the Globus toolkit. We have built a rewall-enabled Globus-based wide-area cluster system in Japan and run some benchmarks on it. In this paper, we report various performance results such as the communication bandwidth and latencies obtained as well as application performance involving a tree search problem. In a wide-area environment, the communication latency through the Nexus Proxy is approximately six times larger when compared to that of direct communications. As message size increases howev...