An easy extension, Verilink adds ISDN to its access device mix >BY CHRIS BUCHOLTZ, West Coast Bureau Chief

A new software component for Verilink Corp.'s Access System 2000 will allow carriers to manage primary rate ISDN on the same platform as asynchronous transfer mode, switched multimegabit data service, frame relay and other types of traffic.

Verilink Oct. 7 introduces the dual-port ISDN Primary Rate Interface 2922, which will let carriers add ISDN capabilities to the AS2000 integrated access device without having to make a major investment in new equipment, said Leigh Belden, president and chief executive officer of Verilink.

The ISDN component, much like other software components for the AS2000, is based on an architecture that allows users to modify the system by "mixing and matching" software modules. This approach lets carriers build integrated access devices that "suit their needs now and can grow to accommodate new services as they are added," said Belden. At the same time, managing a number of services with a single device helps reduce carriers' cost of introducing new services.

The ISDN software solution provides integrated digital access cross-control system and T-1/E-1 access multiplexer functionality to the AS2000. The software also employs call routing and circuit allocation using calling line ID (CLID) and calling line information number (CLIN) features to separate data calls from other traffic and process them more quickly. The approach helps reduce strain on other parts of the public network, Belden said.

"It can relieve switches by off-loading the task of processing call data from the switch," Belden said. "It lets the switch be a switch instead of the front-end processor."

The application also uses CLID to help prevent unauthorized access to proprietary network information. The software verifies CLID information against an internal database within the software module and looks for a call profile match. If no match is found, access is denied.

The CLID feature also simplifies ISDN dial backup, allowing a carrier to automatically or manually restore call information as well as implement time-of-day-reconfiguration switching (see figure).

"As it stands today, it takes multiple products to do this," Belden said. "By tying these functions into the AS2000, we're not only making it less expensive in terms of the products needed to provide the service, but in terms of management and provisioning as well."

One analyst said the ISDN software component will help Verilink compete with other multiservice access device manufacturers, including OnStream, Premisys, Sahara Networks, ADC Kentrox and Digital Link.

"Each new component that's added has the benefit of consolidating another service onto a single multiservice access device," said Beth Gage, an analyst at TeleChoice Inc. "That means [carriers] don't have to find yet another box and they don't have to have five systems and five system operators to keep track of things."

The Verilink system is especially well-suited to new entrants, Gage said. "There can be negatives if the entire network is built around providing 100% ISDN access," she said. "There might be some other, more effective and scalable solutions out there. But the reality for many carriers is that they need a logical strategy to provide a lot of services quickly, and the flexibility of a system like this is very important in doing that economically."