Copper Mountain Has Certified ZyXEL's Prestige 681 as a CopperCompatible Product under its SDSL Interoperability Initiative

Hsinchu, Taiwan, January 19, 2000 Copper Mountain Networks, Inc. (Nasdaq: CMTN) the market-share leader in business Digital Subscriber Line (DSL) equipment, and ZyXEL Communications Corp., (TAI: 2391.TW) an innovator and a leading supplier of DSL customer premises equipment (CPE), today announced that ZyXEL Prestige 681 SDSL Router has successfully passed the interoperability testing of Copper Mountain's CopperEdge(R) 150 and CopperEdge 200 DSL Concentrators. ZyXEL's Prestige 681 SDSL router features symmetric data transmission at selectable speeds, making an ideal high-speed alternative of T1/E1 leased line service for medium businesses seeking to access the Internet or remote office networks. To be certified as CopperCompatible(TM), the Prestige 681 was tested on both architectural and functional levels over varying loop conditions in accordance with SDSL standards. "Achieving interoperability with ZyXEL's SDSL router is part of Copper Mountain's continuous commitment to certify a wide selection of CPE that interoperates with our family of CopperEdge DSL concentrators," said John Nevius, CPE product marketing manager at Copper Mountain Networks. "Copper Mountain initiated the nation's first SDSL interoperability testing program to accelerate Digital Subscribe Line service roll out, meet a wide range of business customer requirements, and drive down costs by promoting effective end-to-end DSL solutions." "The CopperCompatible qualification ensures that ZyXEL's CPE is interoperable with Copper Mountain's central office equipment," said Chinru Lin, Assistant VP of Sales and Marketing Division at ZyXEL Communications Corp. "More importantly, interoperability ensures the possibility of multi-vendor deployment scenarios, which greatly eliminates customer's concerns over compatibility. This successful testing makes ZyXEL's Prestige 681 SDSL router an attractive solution for carriers and service providers who are deploying SDSL services nationwide with Copper Mountain's DSL platform." ZyXEL Prestige 681 SDSL Router Designed for high-speed Internet/LAN access via a SDSL line, ZyXEL Prestige 681 provides symmetrical multi-rate data transmission speeds ranging from 144 kbps up to 2.3 Mbps. The Prestige 681 supports multi-protocol routing for TCP/IP and Novell IPX, as well as transparent bridging for other protocols. Frame Relay support also ensures the Prestige 681's high throughput and reliability for today's bandwidth-consuming businesses. Integrated with ZyXEL's Single User Account (SUA) feature, the Prestige 681 allows multiple users to access the Internet using a single ISP account. SUA supports popular on-line multimedia applications such as NetMeeting, CUSeeMe, IRC, RealPlayer, ICQ, and VDOLive at the same time. The product is easy to install, configure and manage, and has been designed to interoperate seamlessly with major DSL equipment providers. For local pricing and availability, please check with your local ZyXEL distributors or resellers. Copper Mountain CopperEdge Family Copper Mountain's CopperEdge DSL concentrators deliver bandwidth up to 1.5 Mbps while supporting multiple services over DSL, including Internet access, toll-quality voice services, corporate virtual private networks (VPNs), and Frame Relay. CopperView(TM) network management tools provide configuration, fault analysis, and performance monitoring throughout the network from a carrier's central operations center, resulting in substantial savings in time, cost, and complexity in managing DSL equipment network-wide. About ZyXEL Communications ZyXEL Communications Corporation (TAI: 2391.TW), located in Hsinchu, Taiwan, is a leading supplier of broadband Internet access devices, routers, ISDN terminal adapters, and high performance modems. The firm provides complete networking access solutions for Internet/Intranet/VPN/Extranet applications, and also provides networking service solutions in the design, implementation and maintenance of networks for small- to medium-sized businesses. ZyXEL is publicly listed on the Taiwan Stock Exchange (TSE), with distributors in over 70 countries, servicing customers in over 150 countries spanning all seven continents. About Copper Mountain Networks Copper Mountain Networks Inc., (Nasdaq: CMTN) develops and markets a comprehensive family of DSL solutions that enable high-speed internetworking over existing copper facilities. The company's mission is to enable carriers and other service providers to offer a full range of high-performance, cost-effective data and voice services over DSL that are easy to deploy, use, and manage. Copper Mountain's carrier-class CopperEdge(R) DSL concentrators and CopperView(TM) network management solutions offer a robust and scalable platform for carriers and multi-tenant unit service providers to generate a high return on investment while satisfying the ever-increasing user demand for bandwidth.