Management is elementary Tellabs, Lucent move toward full Sonet interoperability >BY BETH SNYDER, Switching & Transmission Editor

Network management is the last bastion against Sonet interoperability. Vendors have figured out how to physically hook each other's boxes to one another and make them work over one network. And similar boxes, such as an add/drop multiplexer from Lucent Technologies and a Fujitsu multiplexer, can be managed across one network. Most vendors have even worked out full seven-layer stack standards compliance for each company's entire line of products.

The final meshing function would be a single network management system controlling different types of equipment from different vendors all in one network.

Lucent and Tellabs had already begun the process last September, along with Fujitsu and Bellcore, when the companies agreed to cooperate on standards-based interoperability. Just a few weeks ago, Lucent and Tellabs took another step, announcing that Lucent's Integrated Transport Management operations support system can fully manage Tellabs' digital cross-connects.

That means a Tellabs Titan 5500 cross-connect looks like a DDM-2000 to the ITM network manager in a Lucent Sonet network of DDM-2000s, said Tom Orlofsky, Lucent product management director. Previously, the Lucent ring could not "see" the Titan. Now the Titan is reading the data communications channel through the Lucent equipment and interoperating with it, he said.

"It's good for the customers," said Mike Arellano, an analyst with Probe Research, Cedar Knolls, N.J. "If you can only add the same vendor's equipment to your Sonet ring, you can't go out to get a competing bid. If you can control Tellabs, Alcatel, Lucent, Fujitsu and Nortel equipment off the same network manager, it means you're not a captive customer.

He pointed out that customers who had wanted assorted vendors' equipment to work together on one Sonet ring had to pay for a customized network management system.

Robert Gadient, analyst with Ryan-Hankin-Kent in San Francisco, agreed that customers are the ultimate benefactors.

"If you think about competition, if you buy a single vendor's equipment, there's always a chance you could get locked into a situation that is not favorable to you," he said. "Crossing over the boundaries either of country or company is a major step toward full interoperability.

The customer can also cut out extra add/drop multiplexers where Sonet rings meet, said a Tellabs spokesman. The cross-connect can now sit directly on the ring between the two. Before, interim ADMs were needed on both sides of the cross-connect.

In the bigger picture, full Sonet interoperability benefits both customer and vendor with network simplicity and efficiency. And the big Sonet players are moving that way.

Fujitsu is also headed in the same direction and is developing integrated element controls for Sonet boxes, according to Greg Wortman, director of marketing.

"In terms of managing other people's boxes, that's something a customer has to decide they want done," he said. "If you want to migrate your network into the future and take advantage of the data communications channel, you have got to have full seven-layer OSI.

Although the Tellabs deal is Lucent's first interoperability with a digital cross-connect, the company would like to work with other DACS vendors, Orlofsky said. Tellabs is already working with Northern Telecom and Fujitsu and will continue to work with others.

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