WorldCom pumps up network strength >BY BETH SNYDER, Switching & Transmission Editor

WorldCom has boosted its frame relay and asynchronous transfer mode backbones to keep up with surging demand. Its frame relay business is growing 20% each month, and the company's ATM customer base now numbers more than 25 businesses and Internet service providers, a WorldCom spokeswoman said.

The interexchange division, formerly called LDDS WorldCom and now part of the newly merged MFS Communications and WorldCom, ordered 27 CBX 500 ATM switches from Cascade Communications for its frame relay network and 29 BPX and AXIS switches from Cisco StrataCom for its pure ATM network.

The upgraded frame relay network will now operate at 622 Mb/s and can carry native ATM. Cascade's OC-12c card is the first to offer the carrier-class feature of automatic protection switching with both an active and standby link, said Chris Baldwin, business manager for ATM products at Cascade.

Worldcom's pure ATM backbone will run at OC-3 speeds and will expand to OC-12 speeds later this year.

"This expansion is just to meet greater demands," said Robert Bentley, senior manager of data engineering at WorldCom. "We're also continuing our trend of having a multivendor approach that helps our customer base. As we keep pushing interoperability, it keeps us flexible in service and equipment offerings.

WorldCom's plan is to eventually integrate its two-vendor frame relay and ATM systems. WorldCom also plans to integrate MFS' frame relay into the ATM backbone for faster end-to-end customer service and simpler network management, Bentley said. However, the former UUNet division has not been scheduled yet for the same type of integration because of its large size.

When WorldCom started as WilTel back in 1991, it began using StrataCom IPX switches for its frame relay network. In 1993, the company added Cascade switches to its domestic frame network and began shifting StrataCom switches to its international system. Today, WorldCom's pure ATM system is mostly Cisco StrataCom BPX equipment, and its frame network is mostly Cascade B-STDX/CBX equipment.