Applied Digital Access and Lucent Technologies Ink Sales Referral Agreement; Strategic Partnership Leverages Best-of-Class Testing Capabilities.

SAN DIEGO--(BUSINESS EDITORS)--Sept. 21, 1998--Applied Digital Access Inc. (NASDAQ:ADAX) announced today that the company has signed a sales agreement with Lucent Technologies Inc. (NYSE:LU) with respect to certain testing products.

As a result, Lucent will be able to provide current customers with a cost-effective and seamless migration path from its Remote Measurement System (RMS) to ADA's Centralized Test System (CTS) product while maintaining their current Switched Access Remote Test System (SARTS) infrastructure. Additionally, the agreement will enable ADA and Lucent to jointly offer a comprehensive testing solution when bidding on new opportunities.

Applied Digital Access is a leading provider of Network Performance Management products that include systems, software, and services used to manage the quality, performance, availability, and reliability of telecommunications service providers' networks. These products enable telecommunications service providers to improve quality of service, increase productivity, and lower operating expenses.

The company, with headquarters in San Diego, has product development and support facilities in Vancouver, British Columbia, Terre Haute, Indiana, and Richardson, Texas. Press releases and other information about Applied Digital Access and its products and services are available at http://www.ada.com on the Internet.

"Safe Harbor" statement under the Private Securities Litigation Reform Act of 1995: Except for historical information contained in this release, the preceding may contain forward-looking statements that involve potential risks and uncertainties as detailed in ADA's Annual Report on Form 10-K for the year ended 12/31/97, which include fluctuations in quarterly operating results, history of losses and the most recent 10-Qs, competition, concentration of major customers; telephone company qualification requirements, high dependence on two product lines, management of changing business, customer mergers, rapid technological change and dependence on new products, dependence on suppliers and subcontractors; high inventory levels and need to make advance purchase commitments, Year 2000 compliance, product recall, government regulation, potential competition from RBOCs, proprietary technology, dependence on key personnel and volatility of stock price. The company's actual results could differ materially from those discussed in this release. Readers are cautioned not to place undue reliance on these forward-looking statements which speak only as of the date hereof. The company undertakes no obligation to revise or update these forward-looking statements to reflect events or circumstances after the date of this release.