ANAHEIM, Calif. -- OFC2001 -- Quantum Bridge Communications Inc. this morning announced a new product that adds dense wavelength-division multiplexing (DWDM) technology to its portfolio.

It's the latest in a string of moves by the company to diversify the range of technologies used to extend optical networks into offices and residences -- the "last mile" of a telecom network. Quantum Bridge has already added Ethernet, T1/E1, and ATM (asynchronous transfer mode) connectivity (see Quantum Bridge Slots In ATM and Quantum Bridge Moves Beyond PON) to its product line.

The QB8000 Optical Edge Switch, announced today, is a 12-inch unit capable of generating eight wavelengths in the C band spectrum at a range of 40 to 60 kilometers. It supports Escon, Fibre Channel, and gigabit Ethernet interfaces, at rates from 51 Mbit/s to 2.5 Gbit/s. It can be configured in ring or point-to-point fashion. Up to four units can be stacked together to create a 32-wavelength system.

This makes Quantum Bridge among the very first access vendors to feature DWDM connectivity at both ends of a passive optical link, which includes the carrier backbone and the customer premises. So far, only one other ATM-based vendor of so-called passive optical networking (PON) products, Terawave Communications, claims to offer DWDM at both ends of the connection.

Although Quantum Bridge says its QB8000 can be used in standalone mode to provide wavelength services to end users, it's clear that the product is designed to work with its other switches, including the QB5000 and QB3000.

The resulting access combination is tailored to telco carriers that are trying to serve business and residential customers with last-mile connectivity. The profile includes multiservice operators, such as cable operators who've already penetrated the home market with Internet access and data services and are seeking to open up their fiber networks to business customers.

"It's a pretty compelling solution," says Rosemary Cochran, principal at Vertical Systems Group, a consultancy. "And for any carrier that's even remotely considering PON, this package has all the right pieces."

The limitation of the QB8000 is that it's small. With just 32 wavelengths, the unit may not be a fit for some large metropolitan network applications.

But Quantum Bridge's customers apparently don't need more than it offers now. "If you take a look at the access applications in demand today, such as aggregating lower-speed links in metro networks, this is fine right now," says Cochran. "And it's probably going to be fine for a while."

-- Mary Jander, senior editor, Light Reading http://www.lightreading.com