ESnet, the Fastest, Most Reliable Lane on the Information Superhighway

May 16, 1996

By Jeffery Kahn, JBKahn@LBL.gov


Puzzled by the recent rash of national news articles about the slowdown of the Internet? If you think these reports lack the ring of truth, it's because of the ESnet, the Energy Sciences Network.

The ESnet is the high-speed network linking DOE Energy Science research and collaborator sites around the globe. When you send or receive information over the Internet, it travels, at least in part, over ESnet, probably the most robust and reliable part of the global Internet.

ESnet along with the National Energy Research Scientific Computing (NERSC) Center is now headquartered at this Laboratory. Jim Leighton, the leader of ESnet since its inception, will manage it here as head of Computing Services' Networking and Telecommunications Department.

Leighton, who has degrees in physics and electrical engineering, began work in networking in 1985. Here, he will oversee an ESnet staff of 20 people. Running ESnet, however, entails global responsibility.

"Managing ESnet is as much sociology as anything else," said Leighton. "In order for the net to work, every laboratory and site on it -- from Berkeley to Brookhaven to CERN -- has to cooperate. We like to say that in terms of the number of sites involved, it's the largest collaboration within DOE."

ESnet is said to be one of the few islands of stability in the chaos of the Internet. There are multiple reasons underlying how ESnet built its reputation for reliability. Leighton says these include a shared ethic of cooperation and excellent two-way communication between users and the network's managers and planners.

Unlike much of the rest of the Internet, the ESnet is a restricted access information superhighway. That is, use is restricted to senders of information who are part of the ESnet community or to those sending information to ESnet sites.

The amount of traffic that a network can handle is referred to as "bandwidth." The more bandwidth, the more packets of information that can be transmitted. Much of the information traveling on the greater Internet is slowed by a lack of adequate bandwidth. That is not the case with ESnet. ESnet is continuously upgraded so that its supply of bandwidth matches or exceeds the growing demand for it. ESnet currently can handle data flows of up to 155 million bits-per-second.

Leighton says that ESnet's roots date back more than a decade. Prior to ESnet, DOE had a 50 thousand-bits-per-second network to link NERSC to its users. Circa 1985, the need for a new network design became manifest. DOE wanted a faster network that also would link all its Energy Research sites. Five years later, ESnet began service with the debut of a T1 (1.5 million bits-per-second) network.

Over its brief history, ESnet has evolved to where more and more of the physical network is provided by private telecommunications vendors. During these years, the number of linked sites and the quantity of traffic has grown dramatically. Leighton says that in order for the network to keep up with the growth in traffic, ESnet has had to play the role of catalyst with the private communications industry.

Helping to shape the future architecture of the Internet, in 1992 ESnet became an advocate of ATM or Asynchronous Transfer Mode. ATM is a standard that allows data, voice, and video communications to travel in a mixed stream through the same network at a very high rate of speed.

"ESnet is not a testbed but a working, production network," explained Leighton. "Yet to keep up with future demand, we must stay on the leading (but not bleeding) edge of technology. In 1992, we realized that the old model of leasing T1 lines connected by routers would not be cost-effective in the future. And so, we became an advocate of a next generation approach called ATM."

ESnet signed a contract with Sprint in September 1994. A year ago, five ESnet sites were linked by the first national production ATM network which ran at speeds of 45 million bits-per-second. Since then, eight more sites including Berkeley Lab have been added, and two sites were upgraded to 155 million-bit-per-second rates. ESnet's successful deployment of ATM has, in turn, accelerated the introduction of this technology into the private marketplace.

This Fall, the ESnet will be upgraded here. At that time, a 622 million bit-per-second ATM test link will be built between here and a Sprint facility in Burlingame.