WINfirst Chooses DSET Gateways for Residential
Fiber-to-the-Home Customers

Bridgewater, NJ - January 2, 2001 - (Nasdaq: DSET) - DSET Corporation, a leading supplier of solutions that enable competitive telecom providers to build an automated Trading Partner Network, announced today that WINfirst will deploy DSET gateways to facilitate the delivery of high-speed voice, video, and data services to residential customers.

Based in Denver, Colorado, WINfirst is building an entirely new fiber-to-the-home (FTTH) residential network to deliver its services. The DSET ezLocal ordering gateway purchased in September 2000 will be used to interconnect electronically with SBC and Pacific Bell in order to automate the migration of customers to the WINfirst network. DSET gateways will also be used to support 911 service and long-distance service for WINfirst's customers.

WINfirst has already received regulatory approval to build network facilities in Sacramento and San Diego, California; and in Austin, Dallas, Houston, and San Antonio, Texas, which combined cover over 3.2 million homes. A temporary permit pending full approval has been received for Portland, Oregon. The company is also pursuing regulatory approval for Los Angeles, Oakland, and San Francisco, California; Phoenix, Arizona; and for the state of Nevada.

"The ability to automate ordering and processing of services is essential in delivering rapid, high-quality end-to-end customer service," said Rich Baugman, WINfirst's vice president of IT. "We selected DSET not only for the operational merits of their systems, but because they shared our commitment to delighting the customer."

"In bringing services directly to residential customers via fiber at speeds starting at 10 megabytes per second, WINfirst is clearly positioning itself as a leader in a new segment of the competitive telecom market," said William P. McHale, Jr., DSET's president and chief executive officer. "This is a very exciting business model because it has the potential to give people at home access to many applications that would have been restricted to business environments due to bandwidth requirements. DSET is proud to be part of WINfirst's groundbreaking effort, and we look forward to the positive reflection in the marketplace."

About WINfirst

WINfirst's fiber-to-the-home residential network combines fiber-optic technology with Ethernet networking standards to break the "last-mile" bottleneck that limits the telecom bandwidth available to most households in the U.S. WINfirst will provide the highest quality of customer service and choice, the convenience of one-stop shopping for Internet, cable TV and telephone service, and the value of a bundled-service offering. For more information, visit www.winfirst.com.

About DSET

DSET Corporation is a leading supplier of software and services that enable telecommunications providers to rapidly implement electronic Trading Partner Networks, which significantly reduce the time required to provision services for customers and resolve service outages to maintain high service quality and ensure customer retention. DSET is headquartered in Bridgewater, New Jersey, and the company's Web site can be viewed at www.dset.com.

Statements regarding financial matters contained in this press release, other than historical facts, are forward-looking. Since all statements about DSET's plans, estimates, and expectations are based on current projections that involve risks and uncertainties, and are subject to change at any time, the company's actual results may differ materially from expected results. Investors should consider these risks and uncertainties, which are discussed in documents filed by DSET with the Securities and Exchange Commission. These documents identify important factors that could cause the actual results to differ materially from those contained in the projections or forward-looking statements. DSET expressly disclaims any obligation to update any forward-looking statements.

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DSET Contacts:

Media Relations: Dean Maskevich, Marketing Communications, 908-526-7500 Ext. 1366,
e-mail: dmaskevi@dset.com

Investor Relations: John P. Murphy, Westfield Investor Relations, 908-233-1558,
e-mail: westfieldir@worldnet.att.net

WINfirst Contact:

Shiraz Moosajee, Vice President, Business Development, 303-407-1617, e-mail: Shiraz@winfirst.com

DSET and the DSET logo are registered trademarks of DSET Corporation.

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