ADTRAN Delivers Unprecedented Multi-Site Dial Backup for Frame Relay at up to 1.5 Mbps Each; Safe-T-Net Solutions Expanded to Support Multiple Sites Using Primary Rate ISDN.

ATLANTA--(BUSINESS WIRE)--Sept. 14, 1999--

ADTRAN, Inc. (Nasdaq:ADTN) today introduced the newest in its Safe-T-Net(TM) family of disaster recovery solutions - high-bandwidth Frame Relay dial backup. The IMUX-56/64 solution for the ATLAS integrated access system offers customers the ability to back up their Frame Relay networks at normal business speeds. Rather than dropping to slower network speeds for disaster recovery, this new solution allows four megabits of bandwidth to be aggregated as needed to support multiple sites, including:

-- 32 sites at 128 kbps

-- 16 sites at 256 kbps

-- 10 sites at 384 kbps, and so on, up to

-- 2 sites at 1.5 Mbps each.

This kind of bulletproof network is essential in today's age of e-commerce and massive online business transactions. No one knows that more than Morgan Keegan and Company, one of the south's largest full-service investment firms, that has already installed the ATLAS IMUX-56/64 solution. The firm's 42 remote offices in 13 states all rely on a critical connection to Reuters stock quotes.

"Our application requires an enormous amount of bandwidth for backup," said Jim Lockett, Senior Technical Engineer at Morgan Keegan. "Every piece of data we miss would mean a significant loss of money. It's mission critical to stay connected if we want to stay in business. I have not seen another product in the industry that can give us this level of protection."

"Previously, companies had to settle for backup operations at speeds much slower than their primary circuits," said Leslie Conway, Director of Marketing for the ADTRAN Enterprise Networks Division. "With the ATLAS IMUX-56/64 BONDing solution, corporations stay alive by restoring their critical network links at appropriate speeds. That means users across the entire WAN can maintain their normal business connections without disruption."

According to Lockett, the ATLAS IMUX-56/64 restores his data link within ten seconds. The inverse multiplexing capacity of the module can be allocated according to the user's needs. The BONDing capability combines multiple ISDN B-channels to support high bandwidth applications, such as dial backup of Frame Relay or dedicated circuits. The IMUX-56/64 solution fits into ADTRAN's ATLAS multi-service platform, a modular, highly scalable system supporting voice and data applications at corporate host sites.

Another New Safe-T-Net Offering

ADTRAN also offers a PRI field-upgradeable dial backup solution for the TSU IQ and TSU IQ+ series of T1/FT1 frame aware DSUs. This product, also featuring ADTRAN's Safe-T-Net technology, can back up 23 sites simultaneously at 64 kbps.

Pricing and Availability

The ATLAS IMUX-56/64 Module is available now for a list price of $1,995. The PRI Module for the TSU series will be available in November 1999 for a list price of $995.

About ADTRAN

Established in 1985, ADTRAN, Inc. is a leading provider of network deployment and access solutions for delivering today's digital telecommunications services over existing copper infrastructures.

Today, 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, xDSL, ISDN, and wireless transport. In the carrier network and enterprise markets, ADTRAN produces a complete end-to-end solution that provides the greatest network efficiency and lowest possible telecommunications costs.

According to Dataquest and IDC, ADTRAN holds revenue-leading positions in the Integrated Access, Frame Relay/DDS, ISDN Extension and HDSL/T1/E1 network and access 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), 256 963-8000, or via e-mail at [e-mail]. On the web, visit www.adtran.com.