Battle of the Ages - Optical Ethernet: a dead ringer for SONET?
01-03-2002
Jared Bazzy, associate editor
telecomflash.com
If there's an access technology that's done nothing but grow, it's Ethernet. With ease of use, low cost and open standards, Ethernet has been so hard to beat that service providers have begun provisioning it to business customers. Ethernet would seem a shoo-in as a potent, nimble tool for service providers seeking to add more value in metro optical networks.
But Ethernet's use in the metro faces a complex challenge: SONET. With SONET's domination of the existing metro landscape, Ethernet will almost certainly have to work with SONET in some networks while simultaneously trying to emulate its carrier-class reliability in others. As a variety of solutions compete for architectural predominance, equipment sales have seen little traction, and analysts remain aloof regarding the industry outlook.
Nonetheless, at least one entrant in the free-for-all underway said that SONET's days are numbered. "I'm not saying SONET is going to disappear tomorrow, but it will be replaced eventually," said Nan Chen, president of the Metro Ethernet Forum and marketing director of Atrica, whose optical Ethernet edge, aggregation and core switches were developed to give carriers an end-to-end optical solution using none of the existing SONET infrastructure. According to Chen, history has lead competing technologies on a path toward convergence. "So where Token Ring, FDDI and other technologies have gone--toward Ethernet--is also the destination of SONET and resilient packet rings in metro networks," he said.
While some analysts predict that nearly half of metro infrastructure equipment sold by 2004 could be optical, other reports speculate that this market may not play out for five to 20 years. So planning for the time when a pure optical Ethernet solution can replace SONET is a risky venture. And while analysts are known to say, "never bet against Ethernet," no one is ready to say, "bet against SONET."
"Nothing beats the economics of something that's paid for," Current Analysis consultant Dave Dunphy said, looking at the issue from the ILEC perspective. The market today is sluggish, he said, noting that in these difficult economic times, carriers want to maximize their existing infrastructures before moving quickly to a new technology, even if its economics look good on paper. Not only are some SONET networks just beginning to pay off, Dunphy said, in perhaps as many as a third utilization is so low that returns have yet to be realized.
He cited the absence of industry-wide standards as a deterrent to a pure Ethernet solution. "When people talk about Ethernet in the MAN, they're talking about Ethernet and some other things…. packet rings, MPLS and Ethernet," Dunphy said.
Neither packet rings nor MPLS are standardized, and while Ethernet's standard has held its own, 10 Gigabit Ethernet is not standardized either. "The last thing anybody wants to do is forklift a network with a nonstandard technology," Dunphy said. |
