Gigabit Ethernet Goes Carrier Class
The module will encourage ISPs and carriers to use Gigabit Ethernet switches rather than routers to build long distance IP backbones, because they'll reap big savings on equipment and operating costs at the same time as speeding up provisioning times.
It's all done by running Gigabit Ethernet over Sonet (synchronous optical network), sidestepping previous distance limitations of running the LAN protocol directly over fiber. IP services based on the scheme will also benefit from Sonet's much vaunted reliability, based on its automatic rerouting of connections around line failures.
Sycamore's module enables two Gigabit Ethernet connections to be supported over an OC-48 (2.5 Gbit/s) Sonet wavelength. The equipment that the module fits into uses DWDM (dense wave division multiplexing) to support multiple OC-48 wavelengths on a single fiber. It comes with management software that enables carriers to provision wavelengths and Gigabit Ethernet connections from a remote console in a matter of minutes.
Right now, the jury's still out on whether Sycamore's new developments will live up to their promise. The vendor won't ship its new module until next quarter and so far, only one startup carrier, Sweden's Utfors AB http://www.utfors.com has said that it will offer services using Sycamore's new equipment.
Utfors plans to build "the world's largest Ethernet network" comprising 6,000-7,000 kilometers of fiber spanning southern Sweden, Denmark and Finland, according to its CTO, Sten Nordell.
Using Sycamore equipment and Gigabit Ethernet switches "is the cheapest way of running IP over fiber," says Nordell. "We'd have to pay $100,000 for a packet over Sonet interfaces for a router. With Gigabit Ethernet switches, the same thing only costs $10,000."
Moreover, Sycamore packs two Gigabit Ethernet connections into an OC-48 wavelength. Without Sycamore's new module, Utfors would only be able to run a single Gigabit connection over a wavelength, halving the amount of bandwidth its fiber can support.