News Archive

Record Bandwidths Achieved Across the CASA Gigabit Testbed Network

Published 11/14/1994

The CASA Gigabit Testbed has achieved record throughput for transmission of data across a wide-area network using the TCP/IP protocol. Between a CRAY Y-MP at the Los Alamos National Laboratory (LANL) and a CRAY C90 at the San Diego Supercomputer Center (SDSC), transmission rates for TCP/IP were measured up to 550 Mbits/second. Since the path separating the computers was approximately 2,000 kilometers, this required sustaining 2 MBytes of data in flight over the fiber-optic channel. Bandwidths up to 578 Mbits/second were measured for the UDP protocol. Using test equipment, bandwidths up to 792 Mbits/second were measured for the raw HIPPI protocol. These bandwidths are the maximum that could be sustained by the CRAY computers, indicating that the wide-area network did not limit the achievable bandwidth.

The CASA Gigabit Testbed links computers at LANL, SDSC, Caltech, and the Jet Propulsion Laboratory via multiple OC-3 SONET channels provided by US West, MCI, and Pacific Bell. Gateways developed at LANL link up to seven OC-3 channels to HIPPI networks at each site. The record bandwidth was achieved by striping HIPPI local-area networks through the LANL gateway across seven OC-3 channels.

The CASA project was funded by NSF and ARPA through the Corporation for National Research Initiatives. The principal investigators are Paul Messina (Caltech), Larry Bergman (JPL), C. Roberto Mechoso (UCLA), Hans-Werner Braun (SDSC), and John Morrison (LANL).

For more information, contact:
Bilal Chinoy
San Diego Supercomputer Center
(619)534-5077 (FAX)