Long-haul WDM connectivity's alive and well on North American networks, according to a recent report from PointEast Research LLC.

The firm surveyed more than 30 carriers, including IXCs, regional carriers, and independent telcos offering long-haul services, from December 2002 through January 2003, gathering details on the levels of utilization for 1,161 Wavelength Division Multiplexing (WDM) city-to-city links or routes.

The report defines "utilization" as "the ratio of lit capacity to deployed system capacity... of a WDM system."

According to principal analyst Brian Van Steen, 41.8 percent of the total capacity within those links has been lit. Forty-two percent are showing utilization levels over 50 percent. Interestingly, though, better than 38 percent of the available capacity is less than one-quarter activated.

Carriers interviewed reported significant growth in utilization over the past year, Van Steen says, despite the rollback in capital spending. "Nothing's happened, while traffic continues to grow," he notes. In general, carriers have added line cards to existing WDM systems to keep pace with demand.

PointEast also asked carriers to name the vendors they were using on each connection. Carriers reported using equipment from Nortel Networks Corp. (NYSE/Toronto: NT) on 450 of the 1,161 connections, while Ciena Corp. (Nasdaq: CIEN) gear was deployed in 330.

Almost all Nortel lit capacity is operating at 10 Gbit/s, while Ciena-based links are generally 2.5 Gbit/s, Van Steen says. Of the Ciena-based links, 48.1 percent are in use; of the Nortel-based ones, 44.1 percent are lit.

On average, routes tallied in the survey have a capacity of 70 wavelengths, or 35 channels, of which 28 wavelengths or 14 channels have been lit.

Van Steen says the survey will be updated every six months, enabling the research firm to provide a view of capacity utilization trends in North America.

— Mary Jander, Senior Editor, Light Reading