Gig-E Breaks free

It's a banner year in the LAN. Gigabit Ethernet is rolling into the enterprise as an enviable package of high speed and low cost. For months, headlines have announced new products and services that eclipse megabit speeds in seemingly painless upgrades to gig-E.

To be certain, ATM and Sonet alternatives aren't heading for the hills - yet. These perennial workhorses still corner the management market for quality and reliability. But the industry push for IP over Ethernet is encroaching on the sacred cow of five 9s reliability, promising a day when quality of service (QOS) can be guaranteed for data and voice.

Meanwhile, gig-E is blazing a migration trail from its 1.25 Gb/s entry point up to a new standard of 10 Gb/s. Enterprise customers are the first line of beneficiaries in this race to take a pure Ethernet play out of the LAN and metropolitan area networks (MANs) and into the WAN.

Virtually every flavor of carrier - from interexchange carriers (IXCs) and ISPs to incumbent and competitive local exchange carriers (ILECs and CLECs) - is jumping on the gig-E bandwagon in hopes that the billion-bit-per-second parade won't pass them by.

No stranger to the street

As a 20-year-old technology, Ethernet is no novice. It matured in LANs, scaling up from a 10 megabit coaxial-based network in the 1980s, to a copper-based application, then to 100 megabits in the mid-1990s.

Ethernet proliferated virtually unchecked by competing protocols. Today, approximately 95% of the world's LANs are connected via Ethernet, roughly 50% over fiber and 50% on copper. By 2003, IDC expects that to escalate to 97%.

"Everybody, including myself until 10 years ago, was touting ATM to the desktop," says Kamran Sistanizadeh, vice president of network architecture for Yipes Communications. "But ATM to the desktop did not materialize because of the emergence of 100 megabit Ethernet to the desktop. And similar things are happening now with 1000 megabit [1.25 gigabit]."

Yipes was one of the first service providers to deliver scalable Ethernet services in the LAN, MAN and, most recently, in the WAN. With plans to deploy a nationwide network by the end of the year, the company currently offers connectivity from 1 Mb/s to 1 Gb/s in nine U.S. cities (Figure 1).

"If we look from the customer premises toward the network, applications are written on IP and the LAN is driven by IP over the Internet. So why not just extend that premises environment into the core environment?" Sistanizadeh asks. "Why only work from the core to the desktop? We are trying to go from the desktop toward the core where the distributed intelligent environment of the enterprise does not get impacted too much by the introduction of new boxes and new technology."

Compatibility is one of the primary attractions to gig-E. It is less complex than its rivals and is backward-compatible with the vast amount of legacy equipment already invested in the LAN. And with more than 20 years in the market, Ethernet is a familiar technology to the IT community. There is a broader staff base that is proficient with the technology, which is compatible with both time division multiplexing (TDM) and wave division multiplexing (WDM).

But the relative cost for the high-speed access is probably the most compelling argument in favor of gig-E. Currently, it is 7% to 10% more costly to run ATM/Sonet as an underlying technology than using IP over Ethernet for a similar transmission, Sistanizadeh estimates. That differential cost is expected to inflate to 40% or 50% during the next year as more ports of gigabit are produced and their cost erodes.

"The major driving force behind any technology traditionally has been profitability," says Carlos Zaidi, senior strategic marketing manager for 10 gig Et hernet at Nortel Networks. "Economics is really what drives technologies and how network architectures change. So the cost and complexity of ATM vs. gigabit Ethernet is far greater, making Ethernet the hands-down winner when it comes to economics. In terms of quality of service, ATM is traditionally seen as the winner."

Ethernet won out in the enterprise space because of economics - that is, infrastructure and operational costs, Zaidi says. "It is simpler and easier to manage the interface. And finally, but not least, are the human capital costs and the ability to hire IP staff. The turnover of IP staff is quite significant."

The main refrain

General consensus acknowledges Ethernet as the dominant LAN technology and gives a nod to companies such as Yipes that extend gig-E's reach into the MAN and even the WAN.

But a mix of diverse players is entering the fray, drawn by the unusual combination of high speed and low cost.

Last October, BT and Lucent Technologies unveiled what they coined as the world's first gigabit Ethernet link running over dense WDM (DWDM). The 107-kilometer link connects Cambridge and Martlesham, England, at 1.25 Gb/s.

"To date, Ethernet has been viewed as relevant only in the local area network environment," says Mary Clarke, Lucent's U.K. director for BT. "In collaboration with BT, we have brought gigabit Ethernet to the wide area network environment by running it over a long distance."

On the domestic scene, long-haul carriers use gig-E to make a quick connection directly into customer facilities.

"We are seeing a fundamental shift in that almost every IXC is building out [gig-E] metros off their backbone," says Near Margalit, chief technology officer and founder of Zaffire, a manufacturer of optical switch platforms for metro and regional networks. Zaffire designs its own amplifiers, which handle point-to-point and ring topologies.

"IXCs want to offer very high-speed connectivity to their customers," Margalit says. "There's no way for their customers to reach that kind of [1.25 Gb/s] bandwidth using traditional technologies such as the incumbent exchange carrier access loop."

The IXCs are trying to build upon price by creating new price points for really high-speed connectivity such as gig-E, Margalit says. "It basically ruins their whole price structure to have to use an RBOC as an access technology to their customers."

The IP infrastructure of Juniper Networks' and Zaffire's platform joined forces for a field trial of its equipment on the BroadBand Office metropolitan optical network.

Williams Communications currently is testing the Zaffire optical services platform running at 5 Gb/s from four metro sites.

"One of the challenges that long-haul carriers have is getting their bandwidth from the incumbent exchange carriers," says Rob Keil, Zaffire's vice president of marketing. "Trying to take a gigabit Ethernet into a Sonet hierarchy is extremely cumbersome. A gigabit channel doesn't fit well into anything other than an OC-48. It doesn't fit into an OC-12 or an OC-3. So, it's very difficult to map the one world of gigabit Ethernet into the other world of Sonet in an efficient way. You can do it; it's just not very efficient and uses up a lot of bandwidth."

Carriers such as Williams want to be more efficient in how they tap the capacity that they have in optical technology, Keil says. "They can leverage DWDM and get a much lower cost end point to their customers via gigabit Ethernet directly to their customers."

An issue that has plagued optical networks is distance and the cost of optical amplifiers needed to boost a signal. Sycamore Networks' approach to the metro is to compress the Ethernet traffic, making it palatable for Sonet and somewhat immune to the distance quandary.

"What we wanted to do was build an on-ramp to off-ramp, end-to-end service infrastructure. And the way we've implemented gigabit Ethernet, we can do that," says John McIlwaine, senior product marketing manager for Sycamore. "It's really like three-stage architecture. There's 2 Gb/s Ethernet input ports. So we essentially massage the traffic, differentiate between the streams and multiplex them together. Then we run them through a Sonet framework."

The next entree

The Ethernet seems a natural fit for CLECs. Its economical yet high-speed allure seems tailor-made to draw market share from the incumbent crowd. However, some regulatory pressures also make it well-suited for ILECs.

"It's really attractive to the ILECs initially because of the troubles that they have in a regulatory manner dealing with WAN services," says Pete Dailey, partner and global business manager at Frost & Sullivan. "SBC has interLATA relief in Texas and Verizon has interLATA relief in New York, but they still can't run nationwide services. So MAN services within their franchise area become very popular by virtue of a process of elimination."

These incumbent carriers may also see gig-E as a necessary step on their way to offering a full suite of WAN services, Dailey says.

SBC was the first ILEC to launch gig-E with its GigaMAN. The service debuted in April in the former Ameritech region for corporate LANs within a 50-mile circumference (Figure 2).

"There's growing opportunity with gigabit, both in terms of what we're trying to accomplish in delivering a service and what an equipment manufacturer is trying to do in delivering equipment as well as with users accepting it," says Joe Simone, SBC's vice president of advanced data. "But when you mention the word `mainstream,' I think of a much more widely accepted offer at a lower speed than gigabit," Simone says. "So is gigabit the next major entree? Absolutely, but it's one that's just at the beginning of its growth curve with a huge amount of upside in front of it," he adds.

But will 80% or 90% of data customers adopt gigabit Ethernet?" Simone asks. "My guess is not for some time to come. I think it will be the middle of the decade before it's a widely accepted technology. It's probably in round 2 of 10 in its growth curve."

However, SBC believes gig-E is a major technology that will be accepted widely over time, he says. "So we do want to be at the forefront of this curve and that's why we deployed this service. It has very attractive economics."

Hostess with the mostest

SBC recently made a more than $100 million investment in one of the fastest growing sectors in telecom and datacom: Web hosting.

In July, SBC purchased a controlling stake in InQuent, the parent company of hosting services provider WebHosting.com. SBC expects to offer a cornucopia of e-business services along with its e-commerce applications, network security and monitoring. All will be coordinated in its hub for e-business, the newly opened, $50 million Internet Data Center in Dallas.

A lesser-known company actually holds a much stronger leadership position in this arena. Exodus provides a range of services for dot-com and enterprise ventures. Customers will co-locate their network servers at one of Exodus' 22 worldwide data centers (Figure 3). By the end of the year, the 6-year-old company expects to operate 36 data centers, from Stockholm, Sweden, to Singapore and across the U.S.

Currently, 52,000 servers are linked at high speeds to the Exodus broadband network. The young company also offers management and professional services from Web design to network management. Its clientele includes eBay, Hotmail, Lycos and The Weather Channel. Exodus hosts 40% of the world's top Web sites, ranked by total number of hits.

In January, Exodus took the gig-E leap of faith and became the first Web hosting company to offer the service as a standard connection onto its network.

"We actually got a jump on our competition by offering gigabit Ethernet sooner than anyone else because we have a larger installed base and our customers were demanding higher speeds than what we had," says Scott Emo, Exodus' director of product marketing.

"We saw this as an early trend. We offered it first as a standard connection to our customers. And we're having great success with it. Our customers greeted the gig-E offering with open arms."

A question of reliability

Sometimes lost in the fanfare of IP - and now Ethernet - is reliability, or rather the lack thereof. The issue is not that packet data transmissions are unreliable; it is that they cannot quite reach the same high watermark that is used in legacy voice systems. But data is quickly closing that divide.

"From a supplier perspective, the notion of equivalent reliability to a [voice] network with five 9s reliability is not something that any data company can provide today," Sistanizadeh says.

"So we are working with our suppliers to guide them with requirements to provide components that can match the reliability requirements of an SS7 kind of a network." He says that it is going to take six to nine months to reach the five 9s level of reliability. "But today with redundancies that we have in our networks, with control systems, dual power supply and dual fiber, we can provide four nines, or 99.99%, reliability," he says.

That is one issue surrounding the comparative aspect of today's technology vs. the legacy telecom industry," Sistanizadeh says. "But you need to ask the question, `Are we paying $1.5 million or are we paying $100,000 for a given system?' Even if you take into account the effort that needs to be done to provide a highly-reliable system of five 9s, the cost differential is still an order of magnitude less than the legacy systems."

10-G salute

Ethernet lives well into its 20s because it can reinvent itself and adapt to the times. Just as new gig-E networks are debuting in many of the nation's largest cities, the IEEE is busy crafting a standard for the next level of multibillion-bit-per-second transmissions.

While 10-gigabit Ethernet will be backward-compatible and build on the success of gig-E, it is expected to find the most fertile field in the WAN where its transmission rate of OC-192c is prevalent.

Between 2001 and 2003, sales of 10-gigabit Ethernet for the WAN and MAN are expected to soar 2500% percent, totaling $1.8 billion, according to a Nortel report.

"When the LAN market starts to take off in 2003, the market [for 10-gigabit Ethernet] is expected to double to $3.6 billion by 2004," Zaidi says. "It will take Ethernet to an entirely new level with entirely new applications. So 10-gigabit Ethernet fundamentally changes the way Ethernet has traditionally been looked at. It's a shift for Ethernet as a technology, meaning that initial implementation of 10-gigabit Ethernet will be in carrier and service provider networks."

For the network designer with a heavy foot and a healthy heart, the acceleration up the Ethernet chain will be a joy ride of new experiences built on the lessons learned from those who went before.

"All of the alternatives have their strengths and weaknesses," Frost & Sullivan's Dailey says of the variety of data-transmission protocols. "The biggest advantage of gigabit Ethernet is the notion that it is backward-compatible or backward-integrated with the legacy investment in the LAN. I view that as what drives the WAN growth. I also believe that a lot of these disadvantages for gigabit Ethernet are giving the IEEE and the other organizations that are doing development on 10-gigabit Ethernet a heads up on what they have to contend with."