News Release

DIGEX Announces Agreement to Test End-to-End Solutions from Cisco

Leading Internet Carrier to Businesses Addresses Scalability Issue Through Tag Switching
Jan 13, 1996

Beltsville, MD, January 13, 1996 --- DIGEX today announced plans to work with Cisco Systems to research, integrate and test network technologies and services that will form the core of next generation Internet solutions. DIGEX has agreed to integrate and test Cisco's most advanced routing and switching technology and to work with Cisco to enhance the technology's performance and scalability. Through this collaboration with Cisco, DIGEX will rapidly develop and implement the tools necessary to provide its customers an exceptionally fast and reliable Internet backbone. By implementing an end-to-end network system from Cisco, DIGEX can deploy consistent network services made possible by Cisco IOSTM software platforms.

"Our relationship with Cisco translates into a competitive advantage for our customers, all of whom rely on the Internet as a business tool," said Clyde Heintzelman, Chief Operating Officer of DIGEX, Incorporated. "Tomorrow's Internet will be challenged more than ever by the demanding applications of corporate America. DIGEX is committed to providing the national network backbone that will most effectively serve those applications."

Among the new routing technologies being evaluated is "Tag Switching," a multilayer switching technology for scaling router and switch backbones. Tag Switching enables routers to more efficiently manage traffic on the Internet and corporate Intranets. The Tag Switching initiative is among the first projects through which DIGEX and Cisco network engineers will collaborate to ensure that the next generation of Internet technology meets the needs of business customers.

"Tag Switching is the latest in a series of Cisco innovations for scaling all aspects of corporate and service provider networks," said Don Listwin, Cisco's Senior Vice President of Cisco IOS* software and market development. "The relationship between DIGEX and Cisco will offer customers scalable strategic platforms and a distinct advantage in today's Internet marketplace."

"DIGEX is very interested in evaluating Cisco System's new Tag Switching technology," said Ed Kern, Vice President of Network Services at DIGEX. "We believe such techniques offer the promise of much greater scalability and functionality for next generation service provider networks. We will also work with Cisco to develop a common standard at the IETF for such mechanisms."

Tag Switching assigns a label or "tag" to packets traversing a network of routers and switches. In a conventional router network, each packet must be processed by each router to determine the next hop of the packet toward its final destination. In a Tag Switching network, tags are assigned to destination networks or hosts. Packets then are switched through the network with each node simply swapping tags rather than processing each packet. Tag switching can both help service provider networks scale with the exponential growth of the Internet, and also add new traffic management capabilities to such networks.

The DIGEX Gold Ring(SM) national fiber optic network consists of a series of dedicated, clear channel DS-3 fiber-optic rings linking 36 major U.S. metropolitan areas. The DIGEX network was designed to provide the highest levels of speed and reliability. DIGEX points of presence (POPs) are high-speed DS-3 and 100% redundant ("no stub cities"). In addition, the network carries only IP traffic.

DIGEX uses exclusively Cisco routing and switching equipment, combining Cisco SystemsTM proven software technology with exceptional performance, reliability and serviceability. Cisco solutions maximize performance and performance measurement and minimize errors and packet loss.

Cisco Systems (NASDAQ: CSCO) is the leading globalsupplier of enterpriseinternetworking solutions,including routers, LAN and ATM switches, dial-upaccess servers and network management software. These products, integratedby the Cisco IOS(tm) software , linkgeographically dispersed LANs, WANs andIBM networks. Cisco news and product/service information are available atWorld Wide Web site Cisco is headquartered in SanJose, CA.

Headquartered in suburban Washington, D.C., DIGEX (NASDAQ: DIGX) is a leading independent national Internet carrier focusing exclusively on business customers. DIGEX offers a comprehensive range of Internet solutions, including high-speed dedicated business connectivity, corporate Web site management services and other network products. The DIGEX Gold Ring(SM) national clear channel redundant DS-3 fiber network provides highly reliable service for mission-critical Internet applications. Company news and product/service information are available at World Wide Web site

DIGEX is a registered trademark of DIGEX, Incorporated. All other products or company names mentioned are used for identification purposes only, and may be trademarks of their respective owners.

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Cisco IOS and Cisco Systems are trademarks, and Cisco and the Cisco Systems logo are registered trademarks of Cisco Systems, Inc. All other trademarks, service marks, registered trademarks or registered service marks mentioned in this document are the property of their respective owners.