Program Development and Execution Support.- REXEC: A Decentralized, Secure Remote Execution Environment for Clusters.- A Visual BSP Programming Environment for Distributed Computing.- Transparent Network Connectivity in Dynamic Cluster Environments.- Network Router Architecture.- A New Methodology to Compute Deadlock-Free Routing Tables for Irregular Networks.- On the Performance of Up*/Down* Routing.- Extending Dynamic Reconfiguration to NOWs with Adaptive Routing.- System Support for Communication Abstractions.- MPI Derived Data Types Support in VIRTUS.- Fast Collective Communication Algorithms for Reflective Memory Network Clusters.- Broadcast/Multicast over Myrinet Using NIC-Assisted Multidestination Messages.- Network Software and Interface Architecture.- Simulation Studies of Gigabit Ethernet Versus Myrinet Using Real Application Cores.- Comparison and Evaluation of Design Choices for Implementing the Virtual Interface Architecture (VIA).- Efficient Communication Using Message Prediction for Cluster of Multiprocessors.