BOSTON - WorldCom* [NASDAQ: WCOM] has 'gone live' with the world's highest capacity in-service network, powered by a high-performance Optical Internet solution from Nortel Networks* [NYSE/TSE: NT].

Capable of providing much-needed bandwidth to metropolitan areas, the WorldCom optical network can now carry up to 1.6 terabits of traffic per second on a single, hair-thin strand of fiber, setting the stage for a new era of networking and managed optical services that can help position service providers to realize potential new revenues. The New York City to Washington D.C. leg of WorldCom's new terabit network was the first to be lit.

"WorldCom is proud to bring our customers the world's highest capacity network," said Fred Briggs, chief technology officer, WorldCom. "This network, powered by Nortel Networks OPTera* Long Haul 1600 Optical Line System, increases our capacity exponentially, allowing us to be one of the first carriers to truly accommodate the nation's bandwidth demands resulting from explosive growth in e-commerce."

"First mover initiatives like this from WorldCom are the type of bold steps needed to thrust the high-performance Internet and next generation services into reality," said Greg Mumford, president, Optical Networking, Nortel Networks.

"Nortel Networks Optical Internet solution will position WorldCom to introduce more managed optical services on a single fiber - like 16,000 fast Ethernet or 1,600 gigabit Ethernet connections - and to redefine the economics and quality of communications," Mumford said.

WorldCom's new network uses Nortel Networks OPTera Long Haul solutions, as well as the OPTera Connect portfolio and Nortel Networks Preside* serviceware. Operating on a 10 gigabits per second (Gbps) platform, OPTera Long Haul uses dense-wavelength division multiplexing (DWDM) to split light into as many as 160 channels to maximize capacity on each fiber. Using Preside, provisioning of these wavelengths takes just minutes to complete. Already being used to manage more than 30,000 elements within WorldCom's network, Preside also enables 'point-and-click' provisioning of services, performance monitoring and troubleshooting, among other services.

Nortel Networks and WorldCom have worked together for many years to move the industry from gigabit per-fiber networking to terabit levels. In September 1995, WorldCom was first to commercially trial Nortel Networks 10 Gbps system on its Dallas-Longview route. WorldCom also was first to commercially trial OPTera Long Haul 1600 terabit system on the same route in December 1999.

Nortel Networks has made substantial investments to increase manufacturing capacity to address worldwide demand for optical systems and components. Through these and other first-mover initiatives, Nortel Networks has become widely recognized as the world's leading supplier of high-capacity 10 Gbps systems.

Nortel Networks is a global Internet and communications leader with capabilities spanning Optical, Wireless, Local Internet and eBusiness. The Company had 1999 U.S. GAAP revenues of US$21.3 billion and serves carrier, service provider and enterprise customers globally. Today, Nortel Networks is creating a high-performance Internet that is more reliable and faster than ever before. It is redefining the economics and quality of networking and the Internet, promising a new era of collaboration, communications and commerce. Visit us at www.nortelnetworks.com.

*Nortel Networks, the Nortel Networks logo and the Globemark are trademarks of Nortel Networks. WorldCom is a trademark of WorldCom.