Harmonic convergence

Simplify, simplify, simplify. That's the position GST Telecom is taking with its Virtual Integrated Transport and Access network, and the service provider is using Northern Telecom technology to accomplish its mission.

GST is designing VITA, an integrated voice, video and data network that will support a combination of packet, frame relay and cell technologies on a common asynchronous transfer mode infrastructure. Nortel, with its Passport and Concorde ATM switches and its DMS500 circuit switch, is providing the capability to integrate these different networks on a single networking platform, said Joe Basile, president and chief operating officer of GST.

Here's how GST is building the network: "The ATM box is the gatekeeper," explained Steve Hensley, vice president of data and Internet engineering at GST. All dial-up services except dial-up Internet services come into the DMS500 and are forwarded directly to the ATM device on the edge of the network.

Dial-up Internet services enter the DMS500, are forwarded to the terminal server and then go to the router before reaching the ATM edge device. All dedicated lines go directly to the ATM device. Once the traffic reaches the ATM device, it can connect, via the GST cloud, to other GST central offices, ATM or frame relay networks, the Internet or other carrier networks (see figure).

"The concept is to use an ATM core as the transport layer [to provide] multiservice access [using] the Passport," said Ted Gagnon, WAN marketing manager at Nortel. "We are putting private networks on a common backbone." Because GST is using all Nortel equipment, the network design is a collaborative effort, he added.

The concept of creating a converged network stems from the fact that people maintain multiple voice and data networks that have evolved into somewhat redundant systems, Basile said.

"When we looked at the growth of data service and the way we set up these mutually exclusive networks, we saw an opportunity to reduce cost and gain true economies of scale," he said.

Competitive local exchange carriers tend to be inefficient because they run as many as eight separate and discrete networks for data, voice, frame relay, Internet or interoffice traffic, explained John Bauer, managing director of Jefferies & Co., a New York-based consultancy. Each of these networks terminates in separate boxes at the central office.

"So the central office has lots of boxes with expensive cards," he said. "[CLECs] are required to keep spare cards in case of failures... and they have to train a staff to maintain these boxes.

"More importantly, these networks can't borrow capacity from each other when they need it because they are static and independent from each other," Bauer said. One box takes up less space, it's easier to fix, and theoretically, carriers should be able to dynamically grab bandwidth when they need it, he said.

Not only will the GST system reduce network management, improve network control and enhance bandwidth, but carriers also will be able to tailor their customer billing structures. For example, users could be charged fees for access, throughput or bandwidth on demand.

EASING INTERNET CONGESTION Ascend Communications and Hewlett-Packard Co. are developing the basis for an SS7 carrier signaling network architecture that will optimize routing and processing of Internet traffic across the public network.

A SWITCH IN TIME The Switchex/DVS automated cross-connect switch from NHC Communications allows service providers to deliver DSL services with little human intervention. The switch sits between the subscriber line and the voice, ISDN, T-1 and DSL lines in the CO and automatically switches those services to DSL.