Ethernet in the WAN

America's Network, June 1, 2000 by John C. Tanner

10-Gigabit Ethernet promises to increase Ethernet's maximum bandwidth 10-fold and bring Ethernet from the LAN into the WAN/MAN for the first time -- in just two short years.

Ethernet - the protocol for the local area network (LAN) - hit gigabit speeds around three years ago. Previously, download speeds of 1 Gbps for LAN workstations had been technologically feasible under ideal conditions. However, under 'real-world' office conditions, such speeds were more difficult to demonstrate.

Gigabit Ethernet's strength is its 10-fold capacity boost at the switching level. Such capacity improves short-haul backbone connections between campus LAN switches, for example.

Now, the datacomms industry is preparing to take Gigabit Ethernet to the next level in more ways than one - to 10-Gigabit Ethernet. The aim is not only to accelerate Ethernet's bandwidth capacity by an additional factor of 10, but also to extend Ethernet's reach beyond the LAN and into wide area (WAN) and metropolitan area (MAN) networks.

IEEE AND INDUSTRY EFFORTS

Efforts to develop 10-Gigabit Ethernet began in earnest earlier this year by a task force of the Institute of Electrical and Electronic Engineers (IEEE). The IEEE's High Speed Study Group established the 802.3ae 10-Gigabit Ethernet Task Force that will approve the final version of 10,000BaseT.

A number of IT industry vendors subsequently organized a coalition to develop IEEE 802.3ae. The 10-Gigabit Ethernet Alliance was announced by founding members 3Com, Cisco Systems, Extreme Networks, Intel, Lucent Technologies, Nortel Networks, Sun Microsystems and Worldwide Packets. The alliance's mission is to "accelerate the acceptance and proliferation of 10-Gigabit Ethernet into the networking market."

The charter of the alliance lists several basic goals:

* Contribute technical input to the IEEE 802.3ae task force;

* Promote industry awareness, acceptance and advancement of 10-Gigabit Ethernet;

* Disseminate resources to establish and demonstrate multivendor interoperability; and

* Communicate between suppliers and users of 10-Gigabit Ethernet technology and products.

FUTURE DEMAND

Some might wonder if market demand exists for 10-Gigabit Ethernet. Such concerns have been expressed before, when Gigabit Ethernet was first announced. Yet a year after the first Gigabit Ethernet products hit the market in 1998, Dataquest reported that sales totaled over $1 billion in the second quarter.

International Data Corporation reported earlier this year that Gigabit Ethernet switches represented 479,572 ports and generated $534 million in revenue during the fourth quarter of 1999. While there have been higher quarterly figures for Gigabit Ethernet in the past, IDC notes that the overall LAN equipment market was impacted for the quarter due to a combination of pre-Y2K jitters and declining prices.

The news of 10-Gigabit Ethernet's impending arrival comes at a time when Ethernet is starting to prove itself a powerful force in the LAN, able to compete more strongly with asynchronous transfer mode (ATM) in terms of bandwidth than many observers might have thought three or four years ago.

"The market is in the midst of the Ethernet renaissance," says Bill Hawe, chief technology officer at Nortel Networks. "Ethernet has become the compelling interface across many types of networking equipment and service provider access solutions."

The growth of Gigabit Ethernet has played no small part in this, according to analyst firm The Yankee Group, which says that the emergence of Gigabit Ethernet as an option for connectivity outside the enterprise is rapidly gaining momentum.

According to The Yankee Group, Gigabit Ethernet offers the near-term benefits of higher bandwidth capacity and lower costs for campus environments. There are also longer term benefits, such as quality of service (QoS) value-adds (e.g., management, metering and billing) and the eventual ability to tie MANs to campus networks or WANs with gigabit-capable routers at the network edge.

As for whether Ethernet networks really need a 10-fold bandwidth upgrade, some vendors argue that, as broadband access technologies proliferate, each new generation of applications and services will grow to take advantage of the newly available bandwidth. Put another way, new applications will require more bandwidth because it's available. Some industry observers suggest that LAN/WANs may require speeds beyond 10 Gbps for certain applications over the next two years - speeds as high as 160 Gbps, by some estimates.

Edward Hopkins, 3Com's technology marketing manager, expects demand for the next level of performance offered by 10-Gigabit Ethernet to "increase significantly" over the next year or so.

INTO THE WAN

So what will 10-Gigabit Ethernet be used for? For a start, 10-Gigabit Ethernet's role in the LAN, like 1000BaseT before it, doesn't involve delivering 10-Gbps speeds straight to the desktop. Existing unshielded twisted pair (UTP) wiring in most Ethernet LANs are barely able to handle Gigabit Ethernet now, much less a protocol that runs 10 times as fast. And such results come from offices that have deployed new enhanced Category 5 wiring to the desktop.