CHAMPAIGN, IL -- The National Center for Supercomputing Applications (NCSA) announces the beta release of version 2.0 of its Virtual Machine Interface (VMI) software. VMI is a middleware communication layer that addresses the issues of availability, usability, and management in the context of large-scale SANs interconnected over wide-area computational grids. With VMI, users are able to run applications on distributed clusters that use different types of interconnects to communicate among processors. The current release supports Intel's IA-32 platform running the Linux operating system with support for Intel's Itanium (IA-64) platform planned for the near future. Future releases will also include data striping across heterogeneous networks to achieve higher bandwidth than is available from a single communications interface, and dynamic failover across heterogeneous networks, a feature that will allow a computation to continue running over any remaining network interfaces if the primary interface fails. Features of VMI 2.0 include: Support for multiple communication interconnects, including TCP/IP, Myricom's Myrinet GM, and Mellanox's Infiniband. Support for the industry standard Message Passing Interface (MPI) parallel computing API, enabling many existing codes to run in a cluster environment simply by recompiling. MPI support is based on MPICH version 1.2.5 from Argonne National Laboratory. Binary portability of MPI applications across interconnects without requiring recompilation of application software. Remote monitoring and management of the entire VMI middleware layer, allowing a user to track and modify the performance of the communications layer while using an application. Source code is available under a liberal open source-style license that allows redistribution in source or binary form provided that copyright notices and disclaimers remain intact. The release is available for download from the VMI project website (http://vmi.ncsa.uiuc.edu). Access to documentation, a bug reporting tool, and support mail lists are also available at the site.