ADTRAN and Jetstream Partner to Deliver Industry Leading Voice-Over-Broadband Solutions; ADTRAN's Total Access System Further Expands Voice-Over-DSL Interoperability.

Business Editors

HUNTSVILLE, Ala.--(BUSINESS WIRE)--March 28, 2000

ADTRAN, Inc. (NASDAQ:ADTN), the market leader in DSL deployment equipment, and Jetstream, the leader in the voice over broadband market, today announced they have teamed to offer a carrier class end-to-end voice over DSL solution. ADTRAN is licensing Jetstream's VoiceBand(TM) messaging protocol, which will enable ADTRAN's Total Access(TM) system of Integrated Access Devices (IADs) to provide seamless interoperation with Jetstream's CPX-1000 broadband voice services platform.

"We are pleased to join forces with Jetstream to interoperate with their CPX-1000 broadband voice gateway," said Danny Windham, ADTRAN's vice president and general manager, Enterprise Networks Division. "The combination of ADTRAN's IAD strength and experience partnered with Jetstream's leadership in the voice gateway arena will accelerate voice over DSL deployment."

The solution set will feature components of the Total Access system, ADTRAN's flagship family of intelligent access devices that integrate industry-leading loop technologies into high-density, Carrier-Class platforms. ADTRAN engineered these systems for the Competitive Local Exchange Carriers (CLECs) with unparalleled flexibility, service options, and management capabilities. All application software can be remotely downloaded into the product using TFTP or Jetstream's integrated firmware download feature.

"Jetstream is excited to have ADTRAN as a JetPowered CPE partner," said Stephen Gleave, vice president of marketing for Jetstream. "ADTRAN's innovative features, including intelligent call routing and remote management, bring first-class functionality required to deploy voice over broadband solutions."

Jetstream's CPX-1000, the leading broadband voice services platform, offers unparalleled reliability and scaleability. With full NEBS 3 certification, and lab certification of Jetstream's GR-303 protocol with the Nortel DMS, Lucent 5E, and the Siemens EWSD, Jetstream offers Integrated Communications Providers, CLECs and ILECs a strong platform for delivering next generation telco services using today's installed infrastructure.

About ADTRAN

Established in 1985, ADTRAN, Inc. is a leading provider of deployment and access solutions for carrier and enterprise networks. ADTRAN technologies support more than two million local loops worldwide. More than 500 ADTRAN products support all major digital technologies, including T3, T1, E1, Frame Relay, DDS, HDSL, HDSL2 xDSL, ISDN, and wireless transport. According to Dataquest and IDC, ADTRAN holds revenue-leading positions in the Integrated Access, Frame Relay/DDS, ISDN Extension and HDSL/T1/E1 markets. ADTRAN customers include the Regional Bell Operating Companies, interexchange carriers, GTE, domestic independent service providers, corporate end users, international customers and original equipment manufacturers. For more information, contact the company at 800 9ADTRAN (800/923-8726) or via e-mail at [e-mail]. On the web, visit www.adtran.com.

About Jetstream

Jetstream Communications Inc., the company that is Enriching Broadband(TM), is the leading provider of Voice over DSL (VoDSL) equipment to incumbent and competitive local exchange carriers. The company's JetPowered(TM) Voice over Broadband solution is rapidly becoming the standard for integrated voice and data service delivery to the small business and high-end residential communications markets. Based in Los Gatos, California, Jetstream is a privately held, venture-backed company led by a seasoned management team consisting of veterans from both the telecommunications and data communications industries. For more information, see the company web site at www.jetstream.com.