ADTRAN's T3SU 300 Sets New Price Standard for T3 Connectivity; ADTRAN introduces new modular, multiport T3 DSU/CSU.

HUNTSVILLE, Ala.--(BUSINESS WIRE)--May 5, 1998--ADTRAN, Inc. (NASDAQ: ADTN), the industry leader in DSU/CSU deployment, today announced their new T3SU 300, a standalone T3 multiport DSU/CSU. This unit is the price leader in the T3 DSU market and incorporates features typically found in high-end broadband devices. The T3SU 300 provides a cost-effective migration path from T1 to T3 services.

T3 service delivers the same bandwidth as 28 T1s and plays a major role in Internet access services and other high bandwidth applications. This service enables customers to substantially reduce line charges by combining multimegabit services over a single T3 circuit. ADTRAN's T3SU 300, with its ability to provide up to four high-speed DTE interfaces, can connect high-speed bridges, routers, front-end processors and other data terminal equipment over unchannelized T3 services.

"A unique feature of the T3SU 300 is its ability to expand to four data interfaces," says Mark Rigby, ADTRAN's director of product management. "The customer can consolidate multiple high-bandwidth applications over a single T3 line, saving both monthly line charges and the cost of additional terminating equipment."

The T3SU 300 provides a single HSSI interface as well as three option slots that accept additional HSSI or high-speed V.35 interfaces. The HSSI interfaces support rates up to 44.2 Mbps in 75 kbps increments, and the high speed V.35 interfaces support rates up to 10 Mbps in increments of 75 kbps.

Incorporating unique features such as automatic remote unit configuration and automatic time of day bandwidth reallocation, the T3SU 300 ensures that the broadband circuit is always optimized. The T3SU also incorporates SNMP and Telnet for easy integration into a today's managed networks.

Pricing and Availability

The T3SU 300 will be available in Q2 with a list price of $4,245. The optional HSSI Interface Module will be available in Q2 with a list price of $995. The optional High-Speed V.35 Module will also be available in Q2 with a list price of $750.

About ADTRAN

Established in 1985, ADTRAN is a leading provider of total system solutions for delivering today's digital transmission technologies over existing telecommunications infrastructures. The company is best-known for developing cost-effective, high-performance equipment that transforms copper wire local loops into high-speed digital networks. An ISO 9001 registered company, ADTRAN is a top supplier of DDS, ISDN, Frame Relay, T1/FT1 and HDSL products. ADTRAN customers include the Regional Bell Operating Companies (RBOCs) and many of the more than 1,300 independent Telcos in the United States.

ADTRAN also designs and manufactures products for private end users in the customer premise equipment (CPE) market. IDC recently reported that ADTRAN holds the number one market share position for worldwide shipments of DSU products in the DDS multi-rate category, claiming almost 15 percent of the worldwide market. IDC also reported that ADTRAN captured 20 percent of worldwide revenues for T1/FT1 DSU/CSUs. For more information, contact the company at 800/9ADTRAN or via e-mail at [e-mail]. On the web, visit www.adtran.com.

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