With a formal vote held Thursday afternoon, the Institute of Electrical and Electronics Engineers Inc. (IEEE) has approved a proposal for a high-speed Ethernet standard, a move that might -- might -- lead to standardized 100-Gbit/s Ethernet in three years.

The vote was held at IEEE plenary meetings in San Diego, following up a formal Higher Speed Ethernet Call for Interest. (It has to be "higher," since the term "high speed" got used for 10-Gbit/s Ethernet. So does that mean "Extra-Higher Speed Ethernet" will be coming next?)

Passage of the proposal wasn't really a surprise. Vendors at OFC/NFOEC in March were already looking ahead to the possiblity of a 100-Gbit/s standard. (See Ethernet Reaches for 100-Gig.)

Now, there's a chance that Higher Speed Ethernet could be 40 Gbit/s rather than 100. That would allow Ethernet to match the speed of OC768 Sonet or STM256 in SDH. But then again, Ethernet previously jumped by a factor of 10, from 1 Gbit/s to 10 Gbit/s, so another factor of 1 to 100-Gbit/s standard seems logical.

Moreover, fans of 100-Gbit/s Ethernet say the industry should reach for the higher data rate now, before bandwidth growth overwhelms the capabilities of equipment. "It's three years of work either way," says Stephen Garrison, vice president of marketing at Force10 Networks Inc.

In the past year, proponents have become vocal about the need for higher-speed Ethernet standards, and vendors including Force10, Extreme Networks Inc. (Nasdaq: EXTR), Foundry Networks Inc. (Nasdaq: FDRY), and Infinera Corp. (Nasdaq: INFN) already are touting their high-end gear as 100-Gbit/s ready.

The issue is being driven by continued increases in network traffic, particularly as more bandwidth-hungry applications (e.g., video) arise. Experts have said that some key Internet exchange points -- Amsterdam being one -- are saying they could use 100-Gbit/s Ethernet capability right now. (See Ready for 100-Gig Ethernet? )

Proponents tried to get a standard started last year but were turned down. "The IEEE was pretty conservative and had them go off to do a study group first," says Lane Patterson, chief technologist for carrier Equinix Inc. (Nasdaq: EQIX).

For this year's effort, supporters tapped users like Equinix and Yahoo Inc. (Nasdaq: YHOO) for testimonials, gathering evidence that carriers want to see some early signs of 100-Gbit/s Ethernet.

"We don't need it in '06 and we don't need it in '07, but we're going to be awfully nervous if there isn't some pre-standard implementation by '08," Patterson says.

So far, any Ethernet needs beyond 10 Gbit/s have been handled with link aggregation (often referred to as LAG), the IEEE method for combining multiple lines into a single virtual link. This makes pipes of up to 80 Gbit/s possible, but some question how well LAG works beyond that point.

Multiple problems creep in when link aggregation gets too dense, 100-Gbit/s Ethernet proponents say. Aggregation beyond eight ports can be harder to troubleshoot. Moreover, carriers don't like the way link aggregation eats up physical ports. "You end up using so many of the available slots just for trunking to other services," Patterson says.

Patterson sees some large carriers pushing peak loads of 300 Gbit/s per day, and he doesn't see link aggregation being practical at that scale. "It will get quite ridiculous in three to four years," he says.

— Craig Matsumoto, Senior Editor, Light Reading