ADTRAN announces new application modules, select and connect multiple applications to a T1 line.

WASHINGTON--(BUSINESS WIRE)--Jan. 30, 1996--ADTRAN (NASDAQ: ADTN) a leading designer, developer and manufacturer of high-speed digital networking equipment, announced five new modules for use with the company's broad line of T1/FT1 and HDSL DSU/CSUs. The announcement was made at the ComNet tradeshow in Washington, D.C.

"With these new modules combined with the existing line of application modules, the assortment of application combinations available using T1 or HDSL and ADTRAN's T1/FT1 and HDSL Service Units is practically limitless," ADTRAN Vice President of Marketing Danny Windham said.

The new modules and their features are:

NxDBU Module - This module provides for the connection of a dial backup device and permits backup to occur only on the failed portion of the bandwidth without disturbing the remaining bandwidth supporting other applications. In addition, multiple NxDBU modules can be used in the ADTRAN T1/FT1 and HDSL Service Units supporting up to six plug-in modules. This feature is of particular importance in corporate environments where multiple remote sites that must remain on-line are connected to the service unit at the central site.

Multiport DBU Module - This module provides for the connection of an external dial backup device to restore service to multiple ports in the event of a dedicated line failure, up to the bandwidth of the external device. For example, by connecting the ADTRAN ISU 512, which utilizes up to four ISDN lines for 512 kbps of bandwidth, to the Multiport DBU Module, data from different sources can be combined and continue operating through the ISU 512 upon failure of the T1 line.

DSU DP Module - This module eliminates the need for and expense of an external DDS DSU/CSU by performing the same function as well as serving as the network interface. It's an ideal solution for a host site connecting with multiple remote sites utilizing all rate DSU/CSUs.

DSX-1 Plug-On - This plug-on board provides an additional PBX interface and is designed primarily for use with the ADTRAN Drop & Insert Module, which allows the termination of an additional T1 line by the T1/FT1 or HDSL Service Unit.

EIA-530 Module - This module provides an interface for data terminal equipment that utilizes an EIA-530 or RS-449 connection, such as popular audio codecs.

The ADTRAN T1 and HDSL Service Units that utilize the new modules include the TSU 100, a T1/FT1 DSU/CSU accepting up to one application module and one plug-on module; TSU 120, a T1/FT1 DSU/CSU with a standard DSX-1 interface for PBX connection and accepts up to one application module and plug-on module; TSU 600, a T1/FT1 DSU/CSU that also functions as a channel bank as it accommodates up to six application modules and six plug-on modules; HSU 100, an HDSL DSU/CSU accepting up to one application module and one plug-on module; and the HSU 600, an HDSL DSU/CSU that also functions as a channel bank as it accommodates up to six application modules and six plug-on modules.

Previously introduced application modules and plug-on modules provide for the connection of videoconferencing equipment, LAN/WAN bridging equipment, analog phones, an additional T1 line and dial backup equipment.

Company Overview

ADTRAN was established in 1985 to design, develop and manufacture advanced transmission products for high-speed digital communications. In addition to its HDSL product offerings, ADTRAN is the primary provider of DDS and ISDN digital loop products to Regional Bell Operating Companies and many well-known OEMs. For more information regarding ADTRAN and its products, call 1-800-9ADTRAN, fax [phone] or e-mail: [e-mail].

CONTACT: ADTRAN

Stacy Thomas, 205/971-8488 or

Danny Windham, 205/971-8756