DSL Prime: 100 Mbps DSL

DSL Prime has reported on Cioffi before. Now the guy who designed 100 Mbps full duplex DSL just won the Marconi prize, telecom's Nobel.

by Dave Burstein of DSL Prime and Future of TV [May 22, 2006]

Marconi Prize for DSL
Cioffi's next goal: "100 Mbps everywhere! Both directions."
DSL pioneer John Cioffi will be presented the $100,000 Marconi Prize for his work in DSL. Until there is a Nobel Prize in Engineering, the Marconi is the ultimate achievement in communications. Cioffi's Discrete Multi-tone encoding (DMT) enables over a hundred million homes to receive broadband.

Few believed Cioffi and Joe Lechleider in 1990 when they asserted ordinary telephone lines could carry megabits. By 1993, lab tests had proved DSL could work, but few believed Cioffi's second claim, that practical equipment could increase efficiency by splitting the frequency range in multiple tones. Working demonstrations of early DMT gear dissolved the skepticism with high performance, and soon became the worldwide standard.

A decade later in 2003, Cioffi again met doubt when his Fast Net Futures keynote promised 100 megabit VDSL. The next year at Fast Net, Ikanos and Metalink demonstrated working chips; in 2005, the demonstration reached 100 megabits symmetrically. They are now deploying in the millions, especially in Japan and Korea.

There will be a dinner and award ceremony October 12 at the Circus Club in Menlo Park, with previous winners Paul Baran, Frederico Faggin, Andrew Viterbi, Martin Hellman and Vint Cerf among the sponsors of the dinner and the "Unleashing the Potential of Communications" symposium. Tim Berners-Lee, Bob Metcalfe, John Pierce, Len Kleinrock, Whitfield Diffie, Gordon Moore, Bob Kahn, and twenty other extraordinary engineers are other awardees, and several are likely to attend. Cioffi tells me he will contribute his award to ongoing research.

Last year's prize to Claude Berrou was awarded at the Waldorf Astoria in New York, also the location of the Rock and Roll Hall of Fame Induction Ceremonies. Jeff Pulver blogged" The assemblage of Marconi Fellows in the room representing various elements of innovation in the computing and communications industry were perhaps even a more powerful gathering than having the all original members of: The Beatles, The Rolling Stones, The Grateful Dead, Cream together with Bob Dylan, Jimmy Hendrix, and Janis Joplin, all in the same room, in 2005." I hope to make it to California, especially since Jennie is shooting a video for the event.

Several of us hope the next Marconi prize will go to Dave Clarke and David Reed of MIT, whose seminal paper "End-To-End Arguments in System Design" defined the open architecture essential for the growth of the Internet.

Fundamentals of DSL Technology
Golden, Dedieu and Jacobsen edit the new text
While Cioffi deserves credit as the leading DSL engineer, dozens of others have made major contributions. The focus of that work was the T1E1 standards committee, headed by Tom Starr. Starr and Cioffi wrote two standard texts on DSL, along with Peter Silverman and Massimo Sorbara. However, the technology is moving fast, and a new source was needed.

Jacobsen and Golden (both former Cioffi students) are active members of the standards group, and have each written a chapter. They are already working on Volume 2. Gottfried Ungerboeck, who won the Marconi prize for inventing Trellis Coding, wrote a chapter on his work, and 13 others contributed. The book is written by engineers for engineers, which means I understand only some parts.

So I'll defer to Cioffi's opinion, in the preface, "This ambitious collection combines the strengths of the world's most renowned DSL experts."

Copyright 2006 Dave Burstein.
The DSL Prime Newsletter is reprinted with permission.

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