Ethernet History

By eweek  |  Posted 2001-09-10 Print this article Print

When Xerox researcher Bob Metcalfe coined the term "Ethernet" 30 years ago to describe a way to push e-mail from one device to a multitude of others across short distances, he had in mind 1 Mbps traveling perhaps a mile. But as modulators blinked the laser light faster and faster, as fiber became more perfectly cylindrical, as algorithms corrected errors in colliding packets and copper wire was fed steroids, the speeds hopped to 10 Mbps, then 100 Mbps and faster. At those speeds, why not stretch the plug-and-play advantages of Ethernet beyond the local office, engineers pondered, connecting across campuses and metro areas?
The problem is that, with Ethernet, every device sees every frame or packet - so what the protocol gains in familiarity, it can lose in traffic congestion.
Gig-E, formalized as a standard in 1998, raises the minimum size of a frame from 64 bytes to 512 bytes, giving the transmitting device more time to receive a collision warning when traffic is congested. The maximum size is also increased, from 1,514 bytes to 9 kilobytes, improving the throughput time because the switch doesnt have to read as many headers. Recent breakthroughs with Multiprotocol Label Switching bring discipline to traffic engineering on a Gig-E IP network by letting routers read just the first packet in a data stream, then slap a short label on that packet and all subsequent ones in the stream. The MPLS tag speeds up switching, determines the best route for the data stream and assigns it a grade of service. That MPLS-driven differentiated service excites the Gig-E crowd, because offering premium service guarantees over an inexpensive network promises real profits. In addition, the Resilient Packet Ring Alliance is hammering out standards to carry Ethernet frames with the resiliency and low latency of SONET - a crucial threshold if the regional Bells are to embrace the protocol. But both MPLS and RPR are in development, and havent passed muster with the standards bodies. The Metro Ethernet Forum, a new alliance of 51 chipmakers, equipment vendors and service providers, had hoped the MPLS standard could be formalized by next spring, but officials said things are moving more slowly than expected. Until standards are formally adopted, the future of the early Gig-E players is as elusive as, well, ether. Hot Gig-E Products And Services Those risks and uncertainties certainly havent stopped several new vendors and carriers from jumping into the Gig-E and 10 Gig-E markets, though, and they are confident their technologies can take Ethernet to the next level. In May, Foundry "planted the flag" when it began selling 10-Gbps products, putting pressure on others in the marketplace to do the same, said Marshall Eisenberg, Foundrys director of product marketing. The California startup has a 10 Gig-E switch available now for $45,000, potentially blowing the closest competing technology out of the water. OC-192 - the SONET platform capable of 10-Gbps speeds - is typically priced at $200,000. Foundry is collaborating with Lucent Technologies to stretch the 10 Gig-E protocol to 40 kilometers across a metro area - Gig-E reaches just 5 kilometers on single-mode optic fiber - but like its competitors, Foundry is still deploying more Gig-E than 10 Gig-E right now. And the company makes sure its boxes are compatible with SONET infrastructure. Customers using Gig-E now can add 10 Gig-E as easily as adding a blade to their existing chassis, Eisenberg said. "Theyll buy a second set of Gigabit [Ethernet] equipment and deploy it in parallel with existing SONET infrastructure," he said. Among Foundrys 3,300 customers are EarthLink, Exodus Communications, Microsoft, MindSpring, the U.S. Army, the U.S. Air Force and Verio. Foundry has also been involved in a groundbreaking project in Sweden. In May, Swedish carrier Utfors used Sycamore Networks ultra-long-haul transport program and switches from Extreme Networks and Foundry to connect Stockholm to Helsinki using the Gig-E protocol. Utfors plans to offer fixed telephony, office-to-office interconnections and virtual private networks across Scandinavia. Its success should quiet critics who say Gig-E cant scale across a metro area or beyond, said Bob Klessig, chairman of the MEFs Technical Committee. Vendors are also pushing Gig-E technology as a solution for bandwidth-hungry enterprises with optic fiber to their buildings. Verio uses Foundrys Big Iron Gigabit Ethernet switching services for its Web hosting. Verio customer PreviewPort hosts video and voice chats with authors, and is gearing up for Barbara Walters publicity blitz when her book is released in the fall. For PreviewPort, the ability to crank the bandwidth up and down, and pay only for what it uses, is essential, said Susan Bergman, PreviewPorts CEO and founder. "If we have something big going on, we need not just a load balancer, but burstable capability," Bergman said. One episode of capacity overload convinced her to find a more flexible, yet inexpensive, approach. "Weve tried to set it up in a totally scalable way, while keeping our bills as low as we can." RealRead, a Web site-based business that lets people read book excerpts, never knows when a new book will become a sensation that sends a stampede of readers to its Web site. So RealRead turned to Netvein, a service provider that offers quick bandwidth provisioning to its customers. Netvein turned to Qwest, which recently made its Dedicated Internet Access service - based on Gig-E - available in seven major cities. "Were extremely happy with it," said Eric Allen, Netveins chief operating officer. "I can sleep at night knowing that portion of the business is humming." Qwest announced its Gig-E offering in May, and plans to be in 25 cities by the years end. Two years from now, most - if not all - links connecting enterprises to broadband will be made through Ethernet, not the venerable OC-3 (155-Mbps), OC-12 (622-Mbps), DS-3 (45-Mbps) connections of the SONET world, Qwests Capurro said. IP services that save the enterprise money and give the service provider or carrier a chance to make a profit on every customer every month will drive Gig-E sales. Two pioneers of the pure Ethernet play in the metro area are Telseon and Yipes Communications. The fact that venture capitalists enthusiastically shower them with money indicates their potential. Both have fiber-optic rings around 20 U.S. cities, offering customers a way to bypass the local exchange carriers altogether. Yipes brings optics all the way to the end user, and is being very careful about which downtown blocks and suburban office parks have enough potential customers to justify stretching the expensive fiber. In late June, Yipes announced it had optic fiber within 500 feet of 10,000 buildings serving 53,000 tenants in New York. Eight customers and 10 major multitenant units there have signed up for Internet and intercity data services. Meanwhile, vendors are demonstrating that their equipment is compatible with smaller and larger Gig-E switches. Avici Systems - which last quarter doubled its share in its battle with Cisco Systems and Juniper Networks for the terabit router market - demonstrated at SuperComm in July its compatibility with Riverstone Networks RS 8000, using Gig-E as the interface. After their interoperability demonstration, Avici and Riverstone won a deal to roll out voice, video, data and DSL services for Chunghwa Telecom, Taiwans largest service provider. "As data traffic continues to overtake all other traffic in volume, Gigabit Ethernet is able to deliver some pretty tangible economic benefits," said Esmerelda Swartz, Avicis vice president of marketing.


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