Metro DWDM tops NFOEC news: Ciena, Fujitsu, Alcatel display products

The buzz at the National Fiber Optic Engineers Conference was metropolitan area dense wavelength division multiplexing. Scarcely populated a year ago, this market segment has attracted the attention of established transport vendors, lending credence to the work of early entrants such as Ciena Corp. and Cambrian Systems.

"We're shipping our third generation product. Some [companies] are in their first generation," said Steve Chaddick, Ciena's senior vice president of strategy and corporate development. Because of Ciena's lead time and development experience, "we feel like we're ahead" of the competition, he added.

After the ill-fated Tellabs/Ciena merger agreement, Ciena announced a corporate reorganization and a move into the OC-192 (9.6 Gb/s) market. At the show, the company announced an OC-192 interface for its long-haul MultiWave Sentry DWDM system.

"We're adding features to flatten the network," said Chaddick. For example, a router can be "directly connected to the optical transport node." The new interface allows carriers to use Ciena products in metro-long-haul-metro transport. Ciena can support a mix of up to 48 10 Gb/s Sonet channels with 2.5 Gb/s channels running asynchronous transfer mode or Internet protocol traffic.

Cambrian demonstrated D1 video running over its OPTera metro DWDM product. "Carriers want to deliver D1, but it's not a sufficient business case," said Solomon Wong, assistant vice president of marketing. Cambrian added Enterprise Systems Connection (ESCON) and gigabit Ethernet support to OPTera. "With gigabit Ethernet and ESCON, it does more stuff-it builds a better business case," he said. ESCON support "generated a lot of carrier interest."

ESCON, typically used in financial, government and health care environments, will eventually evolve to fiber channel, Wong predicted. "If we use DWDM, we can just change it out" instead of replacing the system.

Both Cambrian and Ciena stressed that DWDM is not simply for fiber relief. "You can build a business case on other services," Wong said. Cambrian products will ship by the end of the year.

Fujitsu, however, is counting on fiber relief at a low cost, said Jay Prichard, marketing manager. Fujitsu unveiled its passive WDM system, Flashwave Metro. Transmitting OC-48 (2.4 Gb/s) signals, it supports bidirectional transmission of eight wavelengths or unidirectional transmission of 16 wavelengths. The catch is that it works only with Fujitsu's FLM 2400 add/drop multiplexers.

"It's not for every bit rate or every vendor, but it's for metro area fiber relief and low cost," Prichard said. According to Fujitsu, the Flashwave Metro system can cost 73% less than a WDM transponder-based system configured with four bidirectional wavelengths. An eight-wavelength system is less than half the cost of its transponder-based counterpart, he said, adding that the company's figures include the narrowband optics necessary for the metro system (see figure).

Pirelli Cables and Systems teamed with Ascend Communications to demonstrate its T-31 OMDS 1632 device working with Ascend's GX 550 Smart Core ATM switches. The system simultaneously transmitted five bit rates on a single fiber: OC-3 (155.5 Mb/s), OC-12 (622 Mb/s) and OC-48 ran over ATM, and OC-12 and OC-48 transmitted over Sonet.

Alcatel introduced several access products for DWDM. The Optinex 1640 LXT local exchange terminal, based on Alcatel's long-haul optical ADM, is designed for metro markets. The 1640's transponders support ATM, IP and frame relay across the DWDM system. Alcatel's 1680 Optical Gateway Manager aggregates lower-speed signals for transport over the optical backbone. The OGM collects and grooms traffic and can forward it to additional rings.

Also in the local transport market, Northern Telecom announced Virtual Path Ring technology, designed as a module for the TransportNode OC-3/OC-12 Express systems. The VP Ring allows ATM switches and digital subscriber line access multiplexers to multiplex ATM traffic over Sonet. Nortel also introduced its Metropolitan Optical Network, a bit-rate-independent and protocol-independent transmission platform, and announced plans to provide terabit communications over a single fiber.