Big Bandwidth at CMU - Case Study: Tech leader takes sensible approach

Joe Mullich PC Week April 28, 1997

To head off this threat, CMU flirted with the cutting edge, considering, among other things, upgrading Andrew with ATM (asynchronous transfer mode) technology. But after careful consideration, an evolutionary approach won out: CMU has eschewed ATM in favor of Fast Ethernet and Switched Ethernet, familiar technology that will allow users to zip around online 10 times faster than before, leveraging the power of the schools' fast-growing intranet.

CMU's infrastructure tack is "a good example of how many companies and educational institutions have settled down and taken a practical approach to building their networks," said Don Miller, an analyst at Dataquest Inc., in San Jose, Calif.

For instance, one student put up a Web site dedicated to the "Star Wars" trilogy, complete with MPEG videos of the films (which CMU shut down because it was a copyright no-no). On a more educational front, CMU's psychology department is running a project with a local hospital to model functions in different parts of the brain: As patients do puzzles, magnetic resonance imaging scans of their brains are sent across the network to the college in real time and analyzed.

Even the humanities are gravitating toward high tech. In a CMU fine arts course, students can create online virtual worlds in which they interact with one another. Plans are in the works to use streaming video as a backdrop.

Great stuff, but hardly the kind of thing the Andrew Network was designed to handle a decade ago. So while most companies still were trying to get a handle on the basics of intranet technology, CMU set out to rewire the campus to accommodate it.

"We wanted to be proactive and anticipate the coming rise in traffic levels and upgrade our network," said Alex Hills, CMU's vice provost for computing services, in Pittsburgh. "If you extrapolate the usage curve, you don't have to be Einstein to figure out pretty soon we'd be in trouble if we didn't."

The result was Network 2000, a project to increase the network's capability without, as Hills put it, "going out on a limb in technology." The original Andrew Network relied on 10 Mbps architecture with fiber feeds into each of the school's academic and administrative buildings. Network 2000 upgrades the links to Fast Ethernet operating at 100 Mbps. At the same time, CMU installed Fast Ethernet switches in each building. This provides a "building backbone" to reduce the number of users on a network segment from 200 to less than 25, said Erikas Napjus, CMU's assistant director for networking. The building backbones compartmentalize traffic within sections of a building, making the network more efficient and reliable.

At the desktop level, Network 2000 gives users a choice of 10BaseT Switched Ethernet, providing each outlet with a dedicated capacity of 10 Mbps, or 100BaseTX Shared Ethernet with a tenfold greater capacity. End users in the various departments pay a one-time fee of $325 or $575, respectively, depending on the amount of bandwidth they need. The networking approach is simple, fast and straightforward.

"There is a lot of talk about ATM in campus networking, but it's not clear if that will happen," Hills said. "Something like ATM to the desktop seems like a risky venture to us."

Hedging their bets

"When you're Carnegie Mellon, everyone expects you to sue the latest and greatest," Hills said. "But like an IS organization in a large corporation, we can't afford to be chasing down the latest hot idea."

By not using ATM, retail hardware costs alone dropped from $10 million to $2 million, according to Napjus. That wasn't the only savings: End users could use $79 Fast Ethernet cards in their desktops instead of $1,200 ATM cards. CMU started deploying Network 2000 in August and has now completed about three-quarters of the buildings on campus.

"With such a large-scale deployment, we expected problems and thought we'd have to do a lot of firefighting," Napjus said. "However, it's been seamless."

At the same time, the IT department constantly explores new technologies. CMU has developed a wireless network, called Wireless Andrew, that serves seven buildings and ties into the main network. It is primarily used by researchers working in wireless areas, but as the technology is proven, it may be adopted for more routine use.

"We do want to push the envelope with technologoy, but just not with our pride-and-job production network," Napjus said. "Often universities get caught up in the latest and greatest, believing the quality of service is critically important today. It's important, but the real big issues are reliability and performance. When a faculty member can't get to a Web server to get the materials to teach a class, the mission of the university isn't being fulfilled."

CMU's approach is catching on. "Now, some of the newest and greatest stuff really is the most familiar," said Miller, Dataquest's chief analyst of networking services. "ATM was and is, to a certain extent, uncharted waters. The shiny new thing, is very familiar, is Switched Ethernet. People understand Ethernet, and it's not a great leap to a shared environment -- it's practical, inexpensive, manageable, well-understood, broadly supported and based on standards."

Best of all, the approach gives CMU flexibility, which makes sense considering how fast networking infrastructure is developing to keep pace with the Internet. Even as some debate the place of ATM, manufacturers are promising 1 Gbps Ethernet switches.

"We've made a decision for the next few years to stick with Ethernet and then to re-evaluate our needs," Hills said. "But nothing we're doing now is foreclosing options for the future."

Joe Mullich is a free-lance writer based in Glendale, Calif. He can be reached at 74777.1235@compuserve.com.