Clusters of workstations/PCs connected by o?-the-shelf networks have become popular as platforms for cost-e?ective parallel computing. Technological - vances in both hardware and software have made such a network-based parallel computingplatform an a?ordable alternative to commercial supercomputers for an increasing number of scienti?c applications. Continuing in the tradition of the three previously successful workshops, this fourth Workshop on Communication, Architecture and Applications for Network-basedParallelComputing(CANPC 2000)broughttogetherresearchers and practitioners working in architecture, system software, applications, and performance evaluation to discuss state-of-the-art solutions for network-based parallel computing. This year, the workshop was held in conjunction with the sixth International Symposium on High-Performance Computer Architecture (HPCA-6). As in prior editions, the papers presented here are representative of a sp- trum of research e?orts from groups in academia and industry to further - prove cluster computing's viability, performance, cost-e?ectiveness, and usab- ity. Speci?cally, we have arranged the contributions in this edition into four groups: (1) program development and execution support, (2) network router - chitecture, (3) system support for communication abstractions, and (4) network software and interface architecture.

Clusters of workstations/PCs connected by o?-the-shelf networks have become popular as a platform for cost-e?ective parallel computing. Hardware and so- ware technological advances have made this network-based parallel computing platform feasible. A large number of research groups from academia and industry are working to enhance the capabilities of such a platform, thereby improving its cost-e?ectiveness and usability. These developments are facilitating the mig- tion of many existing applications as well as the development of new applications on this platform. Continuing in the tradition of the two previously successful workshops, this 3rd Workshop on Communication, Architecture and Applications for Netwo- based Parallel Computing (CANPC 99) has brought together researchers and practitioners working in architecture, system software, applications and perf- mance evaluation to discuss state-of-the-art solutions for network-based parallel computing systems. This workshop has become an excellent forum for timely dissemination of ideas and healthy interaction on topics at the cutting edge in cluster computing technology. Each submitted paper underwent a rigorous review process, and was assigned to at least 3 reviewers, including at least 2 program committee members. Each paper received at least 2 reviews, most received 3 and some even had 4 reviews."