Choice One Communications Deploys Applied Digital Access' Traffic Solution to Help Manage Its Nationwide CLEC Network.

SAN DIEGO--(BUSINESS WIRE)--June 23, 1999--

Customer-Proven and Reliable Solution Factored Heavily in Deployment

Process

Applied Digital Access Inc. (ADA)(Nasdaq:ADAX) a leading provider of Network Performance Management products for telecommunications service providers, announced today that Choice One Communications Inc. has purchased and deployed ADA's Traffic Data Collection and Engineering (TDC&E) operations support system (OSS) to provide an automated solution to collect, process and analyze traffic performance data for its nationwide competitive local exchange carrier (CLEC) network.

The TDC&E system is a next-generation OSS designed to help telecommunications service providers, such as Choice One, predict traffic loads and equipment quantities to meet service-level objectives while minimizing capital expenditures and reducing operating expenses.

The system, via an intuitive, Web-enabled browser interface, supports all major engineering and planning functions including traffic operations and administration, customer marketing studies, equipment servicing, network and switch performance analysis, trending and forecasting, traffic separations and quality of service (QoS).

"The TDC&E system will enable Choice One to interface with its growing network of switches, including the Lucent 5ESS(R), as well as provide engineering and planning functions to help analyze day-to-day operations and future growth of Choice One's network," said Don Strohmeyer, president and chief executive officer of ADA. "The automated traffic performance data collection and processing functions and the intuitive browser interface for generation and distribution of traffic performance reports are expected to enhance Choice One's ability to efficiently and effectively manage network performance."

"The ability of the TDC&E system's reporting capabilities to identify trends in network performance through use of its standard reporting package will enable us to use the system out of the box," said Joe Calzone, vice-president, network engineering and operations, Choice One. "It also provides us with a scalable solution that can grow as our needs dictate. Moreover, the TDC&E system is a customer-proven and reliable solution that we believe can help us deliver the highest-quality products and services to small and medium-sized businesses in our markets."

The TDC&E system collects, processes, analyzes and generates reports of traffic performance data for all major switch manufacturers, including Ericsson, Lucent, Nortel and Siemens. "The customer-proven robust architecture was a key factor in our ability to integrate the TDC&E system into our operations," said Joseph Schaal, vice-president, information technology, Choice One. "In our competitive environment, ease of use and ease of deployment are key factors from both a practical and financial standpoint."

ADA also offers a family of provisioning, fault- and alarm-management, test-management operations systems software, including .Provisioner, which automates digital-circuit and node-provisioning functions; and the Fault Management System (FMS), a scaleable fault- and alarm- management system for real-time monitoring and management of telecommunications networks.

About Choice One Communications

With headquarters in Rochester, N.Y., Choice One offers local telecommunications service, long distance, data, Internet and DSL solutions targeting small to medium-sized businesses in the northeast United States. The company is making significant long-term investments in target markets by deploying Lucent 5ESS integrated switching and data platforms including DSL technology to offer its clients fully integrated high quality solutions for telecommunications services.

About Applied Digital Access

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 has headquarters in San Diego, and has product-development and support facilities in Vancouver, British Columbia and Terre Haute, Ind. Press releases and other information about Applied Digital Access, its products and services are available on the Web at www.ada.com.

"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 12/31/98 and the most recent 10-Qs, which include: customer mergers, fluctuations in quarterly operating results; history of losses, competition, concentration of major customers; telephone company qualification requirements, dependence on two product lines, management of changing business, 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 and defects, 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.