^{Democracy & Technology Blog} Terabit Ethernet coming soon

George Gilder is getting some well-deserved recognition in Technology Review in an article by Mark Williams entitled “The State of the Global Telecosm – The most notorious promoter of the 1990s telecom boom has been proved right.”

“I’m a fan of George Gilder, the bubble bursting notwithstanding,” Ethernet co­inventor Bob Metcalfe (a member of Technology Review’s board of directors) told me after his San Diego keynote speech, “Toward Terabit Ethernet.” Metcalfe had told his audience not only that optical networks would soon deliver 40- and 100-gigabit-per-second Ethernet–standards bodies are now hammering out the technical specifications–but also that 1,000-gigabyte-per-second Ethernet, which Metcalfe dubbed “terabit Ethernet,” would emerge around 2015. Why, I asked, did Metcalfe believe this? “Last night, Gilder spoke to 300 of us at an executive forum about his ‘Exaflood’ paper, in which he predicts a zettabyte of U.S. Internet traffic by the year 2015,” Metcalfe said. “Since I admire Gilder, I extrapolated from his prediction.”
An exabyte is 1018 bytes of data; a zettabyte is 1021 bytes. Metcalfe pointed to video, new mobile, and embedded systems as the factors driving this rising data flood: “Video is becoming the Internet’s dominant traffic, and that’s before high definition comes fully online. Mobile Internet just passed a billion new cell phones per year. Then totally new sources of traffic exist, like the 10 billion embedded microcontrollers now shipped annually.”

Metcalfe also addresses the interesting question of whether there is sufficient capacity in the Internet backbone to accommodate the surging traffic:

Did Metcalfe believe that the existing infrastructure–built in the boom years, when great excesses of fiber-optic cable were laid down–could support terabit Ethernet? “That dark fiber laid down then is being lit up, and some routes are now full,” he said. “That’s the principal pressure to go to 40 and 100 gigabits per second. It seems we can reach those speeds with basically the same fibers, lasers, photodetectors, and 1,500-nanometer wavelengths we have, mostly by means of modulation improvement. But it’s doubtful we’ll wring another factor of 10 beyond that.” Thus, the backbone networks would need to be overhauled and new technologies implemented.