ADTRAN to unveil new application modules for T1 service units at ComNet.

HUNTSVILLE, Ala.--(BUSINESS WIRE)--Jan. 20, 1995--ADTRAN Inc. (Nasdaq:ADTN), a leading supplier of voice and data communications network access devices, will introduce two new application modules for use with the ADTRAN line of T1 service units (TSUs) accepting such modules.

Both modules will be demonstrated at the ComNet Trade Show to be held in Washington, D.C. (ComNet Booth Number 862).

New 2FXO Module

The 2FXO module, placed in the ADTRAN TSU 100, TSU 600 or HSU 100, provides two voice foreign exchange office (FXO) voice ports. This allows the extension of phone lines to a far end TSU containing an FXS Module.

The FXO is also available in a ``plug on'' version designed to be combined with a module, allowing for a wide variety of interface port combinations. The FXO Module and Plug-On are $400 each and will be available March 1, 1995.

New DBU Module

The DBU (Dial Backup) Module provides switched backup for a single port of either the ADTRAN TSU 100 or TSU 600 T1 service units. In the event of T1 circuit failure, the DBU module causes an external DCE to establish a switched backup connection. For the ComNet demonstration, a TSU 100 (hosting an Audio Codec connected to a CD player) and a TSU 600 (hosting an Audio Codec connected to a set of speakers) will be networked and each equipped with a DBU module, which, in a line failure situation, will dial up an ADTRAN ISDN service unit for 512 kbps of backup bandwidth.

The module can be configured to automatically revert back to the primary circuit when it is restored, and to avert backup during specified hours, such as the weekend. The DBU Module is one of several ADTRAN T1 service unit expansion modules that accepts ADTRAN Plug-On Boards.

The DBU Module will list for $545 and will begin shipping mid-March 1995.

Other ADTRAN T1 Products

The ADTRAN TSU 600 serves as a link between T1 network services and data sources such as Local Area Networks (LAN) bridges and routers, computers, CAD systems, teleconferencing equipment and PBXs. By utilizing multiple ports, the TSU 600 can simultaneously connect one or more of these devices to a T1 circuit. The TSU 600 provides six slots designed to accept the same expansion modules currently available for the ADTRAN TSU 100, featuring a single option slot.

Modules can be added to each slot of the TSU 600 providing one or two additional data ports or four additional voice ports for a total of 12 possible data ports, 24 voice ports, or a combination of voice and data up to those limits. The bandwidth allocated to each port is programmable and can be changed manually, or set to automatically change at predetermined times, for optimum usage of the T1 bandwidth.

The FXO and DBU modules are two of several ADTRAN modules available to enhance the TSU 100 and TSU 600's ability to address a variety of applications and to expand as necessary.

Industry analysts estimate that local exchange carriers will install as many as 170,000 dedicated high-speed T1 circuits this year, and predict the T1 market will grow by 15 percent in 1995. A growing number of those lines will support data-intensive new applications such as multimedia and video teleconferencing, thus the requirement to link data channels to T1 lines is growing.

ADTRAN was established in 1985 to design, develop and manufacture advanced transmission products for high-speed digital communications. Today ADTRAN is the primary provider of DDS and ISDN digital loop products to Regional Bell Operating Companies and many well-known OEMs. The broad selection of customer premises products offered by ADTRAN includes a complete line of DSU/CSUs, a variety of ISDN extension and network terminating products and flexible T1 multiplexers. For more information regarding ADTRAN and its products, call 1-800-326-3700, fax [phone] or E-Mail: [e-mail].

CONTACT: ADTRAN, Inc., Huntsville

Stacey Thomas, 205/971-8488

Bill Salmon, 205/971-8618