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Four of the San Diego Supercomputer Center's networking experts - Tom Hutton, Sean Peisert, Ronn Ritke, and Kevin Walsh - played key roles in making a technological miracle happen at SC2003 in Phoenix, Arizona.

Each November, the annual International Conference for High Performance Computing and Communications - otherwise known as SC - comes to a convention center in a new city. In the course of a week some of the brightest people in the country turn vision into reality by stringing hundreds of miles of fiber-optic cable and coaxing millions of dollars' worth of temperamental high-performance switches and routers into running vast amounts of information through these conduits at almost unimaginable speeds. In short, SCinet is born. SCinet is the name of the world's highest-performance network and of the "virtual organization" that creates it, keeps it running for a couple of weeks, and then tears it down only to be re-created from scratch the next year in another city. Perhaps the most amazing thing about SCinet is that it's entirely a volunteer effort. Using the latest high-tech equipment on loan from networking manufacturers, technology experts from universities, network equipment manufacturers, telecommunications carriers, government labs, and high-performance computing sites - including SDSC - work together in a community effort to design and deliver the SCinet infrastructure.

"We are very proud to have contributed the talents of these four experts to the SCinet effort," said Vijay Samalan, SDSC's Program Director for Networking. "They put a lot of hard work into making the SC2003 conference a success, and it's clear that they succeeded." Network architect Tom Hutton played a key role in supporting high-performance data communications between the SC2003 conference and other countries. Hutton's role with SCinet and IPv6 began at SC2000, where he supported the joint efforts of Japanese and SDSC researchers to demonstrate live, interactive inter-continental telescience. By 2003 his duties had expanded to providing "IPv6 everywhere" for the conference. SCinet provided direct wide-area connectivity to Abilene, the TeraGrid, ESnet, DREN, and many national and worldwide networks through peering relationships with these networks, and for the first time IPv6 functionality was available for all of them (and even for networks in the SC2003 meeting rooms and wireless networks). Hutton architected IPv6 networking facilities between Phoenix and Asia, Europe, and South America to support international demonstrations of scientific applications. Several high-profile demonstrations in the exhibit hall - including some at the SDSC exhibit booth - involved collaborations between American researchers and collaborators in such countries as Argentina, Japan, Korea, the Netherlands, Sweden, and Taiwan.

"The governments of Japan and China have designated the IPv6 network protocols as their national standards," Hutton said. "With the increase in collaborative science between American and Asian institutions, it's clear that these protocols will become increasingly more important to the conduct of international scientific research."

Kevin Walsh, Director of the CAL-ITEC Network Performance Reference Lab at SDSC, began his association with SCinet in 2000 through his work with the Grid Forum. He was named Chair of the Bandwidth Challenge competition for this year's SC conference. In the Bandwidth Challenge, contestants from science and engineering research communities around the world demonstrate the latest technologies and scientific applications for high-performance networking, most of which are so demanding that no ordinary computer network could sustain them. At SC2003, the contestants were challenged to "significantly stress" the SCinet network infrastructure while moving meaningful data files across the multiple research networks that connected to SCinet.

Walsh's SC2003 activities started more than a year ago: planning the Bandwidth Challenge competition, soliciting and qualifying the contestants, coordinating with the other network engineers of SCinet, and working with equipment vendors to contribute ultrafast network devices that could measure speed and throughput to determine what the contestants actually accomplished. Walsh traveled to Phoenix for three weeks (November 8 - 22) to set up the measurement and display infrastructure for the Bandwidth Challenge, and to deal with the participants and the media covering the event. He also chaired a panel discussion in the Technical Program on the Bandwidth Challenge, and in addition helped to set up the SCinet network in the Phoenix Convention Center.

"I provided a focus to the Bandwidth Challenge that was different from previous years' events," Walsh said. "The contestants were asked to explain the science behind their entries, their methodologies and techniques, and how their science benefits from high-bandwidth, high-performance networks. Each participant spoke to these areas in their presentations during the Technical Program, and the judges were asked to include this information in how they assessed the accomplishments of each participant."

SC2003 was the second time SDSC Fellow Sean Peisert had contributed his talents to SCinet. He assisted in the Bandwidth Challenge by analyzing and interpreting the data. It's a key task becausethe data packets stream through the system at speeds that push the state of the art. The analyses have to be interpreted in time to announce clear winners, backed up with performance graphs, while the SC2003 conference is still in session.

"I set up the scripts and infrastructure to take the datafiles generated by the Spirent network gear, calculate bandwidth usage, and display a graph of current results every 15 seconds on the Web," Peisert explained. "One of the fun and challenging things about the Bandwidth Challenge is what I call 'coding under pressure.' The scripts to capture and graph information aren't terribly difficult to write, and I came to the conference well-prepared with a working version of the scripts. But by the time I arrived at the conference, there were a bunch of additional requests for features to be added - even new features after two or three contestants had already had run their entries in the competition! As a result, I was frantically revising different versions of the scripts throughout the contest."

Ronn Ritke, co-principal investigator of the Measurement and Network Analysis effort of the National Laboratory for Applied Network Research (NLANR) at SDSC, served as one of the judges of the Bandwidth Challenge competition.

"It was really fascinating to see the teamwork and professionalism of both the SCinet crew and the Bandwidth Challenge contestants," Ritke said. "These people all had incredibly challenging jobs to do, and they performed well."

Ritke accomplished an additional undertaking while he was working with the SCinet team: he took advantage of the fact that the SCinet infrastructure was, for a brief time, one of the most advanced operational networks on the planet, and used the opportunity to embed an AMP (Active Measurement Project) monitoring device in the SCinet Network Operations Center. The AMP device measured the network connectivity (path topologies, round-trip-times, and other parameters) between SCinet and more than 150 other sites across the continent with embedded AMP monitors. Ritke also tested the operation of two advanced-model OC192/10-gigabit interface cards.

"SDSC's participation in SCinet and SC is very worthwhile, because we are a key part of the High Performance Computing community, and our role as a member of this community is to share our experience to advance the capabilities of the community," Walsh said. "Computer science and domain science - physics, biology, chemistry - benefit significantly from high-performance research networks. Cutting-edge science carried out on an international scale is pushing available bandwidth, and projections indicate that Grid computing will drive further increases. Bandwidth has to grow, and we need to learn how to use it wisely. We're helping to make that happen, both at SDSC and at the SC conferences."