HOW TO HARNESS THE BIG GIG-E

In terms of its low cost and ease of use, gigabit Eithernet has lots of advantages. But the technology falls short when its comes to resiliency and network control, and some carriers are still hesitant to roll it our widescale. The answer to taking gig-E to the next level may lie in bringing a wide variety of technologies together for the common good.

The words “cheap” and “easy” aren't often associated with telecommunications networks. But for the old enterprise standby Ethernet, which has turned service provider friendly, people unanimously agree those adjectives are appropriate. So if that's the case, then why haven't service providers blanketed the country with gigabit-speed Ethernet? The answer lies in what gig-E still can't do — and whether anyone is brave enough to work out the kinks.

Fortunately, some negatives of gig-E may be disappearing, although it will likely take creativity and cooperation from vendors and service providers alike.

Ethernet has slithered its way out of its LAN roots and into some service provider networks. And why not? The 25-year-old technology has been proven again and again in the enterprise space and is easily understood by network novices. Using the technology for service provider applications was a natural evolution for a well-liked technology.

The problem is the technology was designed for the enterprise space rather than service provider networks. And while Ethernet is gaining popularity, it lacks certain benefits of technologies such as Sonet. So the challenge is to add the qualities such as network control, scalability and reliability without adding complexity or cost.

Once those issues are addressed, gig-E stands to infiltrate service provider networks in a fashion similar to its takeover of the enterprise.

Of course, the big driver for service providers to use gig-E is new revenue potential. Providers would be able to offer things such as better VPN services, better service level agreements (SLAs) and better transparent LAN services.

“What's interesting is that Ethernet is kind of the wild, wild West,” said Andrew Crabtree, product manager of gig-E services for Williams Communications. “It's really a brave new frontier.”

Now the trick is to tame that frontier. Ethernet “has been known as cheap with no gusto,” Crabtree said. “It's really grown from a best-effort LAN infrastructure to something that is becoming more carrier-grade.”

Others agree that guaranteeing reliability is essential. “With metro Ethernet services, the critical thing that makes it profitable is reliability,” said David Yates, vice president of marketing for Atrica, which is developing Ethernet equipment for the metro core. The company recently announced its optical Ethernet system supports sub-50 seconds restoration for metro networks. “Users say they will pay for higher quality, and end users have shown they will pay good money for reliable service with defined SLAs.”

But mass adoption is still well in the future. “Gig-E is still in the early adoption phase by the carrier community,” said John Kane, CEO of Telseon, which offers metro Ethernet service as well as optical wavelength services.

While an effort to convince service providers to deploy Ethernet in the metro is in full swing, companies are challenged to find ways around gig-E's problems.

“There's no quality of service really built into the Ethernet standard,” Crabtree said. “It's something the standards have been pushing — they want the higher speed and higher quality of service to make it more of a carrier-grade product moving from the LAN and the [metropolitan area network] and eventually the WAN.”

In addition to the task of adding more carrier-grade characteristics to Ethernet, distance also must be addressed. “Ethernet has always had stringent distance limitations,” said Marian Stasney, senior analyst for The Yankee Group. “If you lateral off of a ring more than a quarter of a mile, the chances of doing Ethernet are slim.”

Despite some of gig-E's limitations, providers are working to engineer ways to gain higher QOS with Ethernet in areas such as the long haul, according to Crabtree. “You may be able to add a certain quality of service you might not even be able to get on the metro portion,” he said. “We are looking at the problems inherent to Ethernet as opportunities that we can really jump on.”

Williams is using gig-E as a way to beef up its metro connectivity and is offering it on an intercity basis as well. The provider recently inked a contract with Yahoo in which Williams will deliver local-to-national-to-local Ethernet service to the ISP. Williams has been working with its vendors to devise solutions, although not proprietary ones, that use standards-based approaches in an inventive way.

Now providers must pinpoint the best way to usurp the benefits of Ethernet and expand upon them. And while it's likely that the marketplace will help choose which methods are the most resilient, those solutions must be standardized to inspire widespread adoption.

As Ethernet struggles to find its way across the metro and beyond, technology developers must choose which method solves the most problems and offers the most potential for revenue growth.

Some stand staunchly behind the use of multiprotocol label switching (MPLS), which attaches labels to act as a guide for traffic as it traverses the network. Some support resilient packet ring (RPR) technology that is used in the metro core to boost data handling capabilities in Sonet or dense wave division multiplexing (DWDM) rings. Still others strongly support rapid spanning tree, which is used to add network resiliency on Ethernet rings.

Vendors such as Luminous Networks support RPR because of the technology's ability to improve on protection switching. With Sonet, protection switching is accomplished through wrapping, but according to Raj Sharma, director of technology strategy for Luminous, “There's a lot inefficiency there.”

Yet when RPR is used, a decision can be made based on the availability of bandwidth, Sharma said.

The variety of gig-E technologies may prolong the process of picking a winning solution, but that's not necessarily bad, according to Crabtree. “There are a lot more options and a lot more ways to go with Ethernet, especially on the long-haul side, and there are a lot more toys to play with,” he said.

In fact, a combination of technologies may be the best answer. Occam Networks, a developer of broadband loop equipment, is using MPLS and rapid spanning tree to achieve the cost benefits of Ethernet and the resiliency of Sonet, said Russ Sharer, Occam's vice president of marketing and sales. Occam used the concept of virtual LANs, or VLANs, to create protocols on existing Ethernet networks.

In the metro environment, Nortel Networks has chosen to enable its multiservice platform, the OPTera Metro 3500, to support Sonet, Ethernet over fiber, Ethernet over RPR and Ethernet over DWDM — all on the same platform.

“One technology won't completely dominate,” said Al Safarikas, vice president of optical Ethernet marketing for Nortel. “It could be RPR, MPLS or both.” He added that the network of the future likely will be a hybrid where Ethernet is the common unifier.

Although Williams has a Cisco-powered network, the company also is looking at other vendors such as Riverstone Networks, Coriolis Networks, Appian Communications and Extreme Networks that have more proprietary solutions. Williams' Ethernet product will evolve over the next few years as a multiphased evolution, said Crabtree.

“It's still a very early market and there are going to be a lot of dynamics in the marketplace,” he said. “Developing in that environment is difficult because you are trying to position your product and do market research at the same time. It's an evolving and a moving target.”

Support of a variety of technologies is key, said Telseon's Kane. Some services such as high-speed storage won't work well with Sonet, whereas other services such as voice are better off with Sonet. At this point, if a provider focuses solely on gig-E, its opportunities will be limited, according to Kane.

All in all, Ethernet has earned a stable position in the service provider infrastructures of the future. It just won't necessarily be the only technology used, and according to Stasney, “Ethernet is an excellent option to fill the gaps left by other technologies.”

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With additional reporting by Vince Vittore in Chicago.

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