ISP in Austin Reinforces Allegiance's Data Strategy

DALLAS, February 13, 2001-- Allegiance Telecom, Inc. (Nasdaq: ALGX) announced it has added Jump.Net, an Austin, Texas-based Internet service and collocation provider, as a wholly-owned subsidiary. Terms of the deal were not disclosed.

Based in northwest Austin for more than five years, Jump.Net has carved a market niche with reliable Internet connectivity, enhanced Internet services and top-notch technical support to subscribers, Web hosting clients and collocation customers. As the newest member of the Allegiance Telecom portfolio of companies, Jump.Net will continue to offer its suite of products and services with its existing management team and employees. Jump.Net has 75 employees who have become employees of Allegiance Telecom.

"Jump.Net has extensive experience with broadband and server collocation technologies, making it an excellent fit with Allegiance's growth and expansion plans," said Royce J. Holland, chairman and CEO of Allegiance Telecom. "In combination with several recent additions of similar Internet service companies, Allegiance is even better positioned to provide extensive Internet, Web hosting and e-commerce services for our target market of small and medium-sized businesses."

"We look forward to expanding Jump.Net with Allegiance's extensive resources and capabilities," said Kenneth Smith, co-founder of Jump.Net. "This relationship has tremendous positive implications and mutual benefits for the growth and product diversity of both companies."

Based in Dallas, Allegiance Telecom (www.allegiancetele.com) is a facilities-based
integrated communications provider (ICP) that offers businesses a complete package of telecommunications services, including local, long distance, international calling, high-speed data transmission and Internet services. Allegiance is currently operational in 27 U.S. markets -- including Atlanta, Baltimore, Boston, Chicago, Cleveland, Dallas, Denver, Detroit, Fort Worth, Houston, Long Island, Los Angeles, Miami, Minneapolis/St. Paul, New York, Northern New Jersey, Oakland, Orange County, Philadelphia, Phoenix, St. Louis, San Diego, San Francisco, San Jose, Seattle, Tampa and Washington D.C. -- and is targeting a total of 36 major metropolitan areas (including Austin) with its "one-stop shopping" approach. Allegiance's common stock is traded on the Nasdaq National Market under the symbol ALGX.

Jump.net (www.jump.net) is an Internet service provider that serves approximately 15,000 subscribers and 8,500 Web hosting and collocation customers nationwide.
Founded in 1995 and based in Austin, Texas, Jump.Net is one of Texas' original digital subscriber line (DSL) providers and is one of the few providers in Texas to offer a 100 percent reliability guarantee across all service areas.

Jump.Net was awarded Southwestern Bell's "Top Producer" award for "Alternate Channels in 1999" for its ADSL (asymmetric DSL) sales. Jump.Net was given the Grand Achievement award by the ISPBF (Internet Service Provider Business Forum, www.ispbf.org) at ISPCon (Internet Service Provider Conference) in San Jose, California on November 8, 2000 for its trail-blazing achievements in the DSL space. For more information, visit the company's Web site at www.jump.net or contact Jump.Net at 877-JUMPNET or fax 512-257-4701.