OPNET and Comsof Complete Joint Venture and Announce New WDM Guru Product for Optical Network Design

BETHESDA, MD and GHENT, BELGIUM --August 20, 2001 -- OPNET Technologies, Inc. (Nasdaq: OPNT),the leading provider of intelligent network management software, and Comsof, a Belgium-based software company with world-class expertise in optical network design, today announced the completion of a joint venture and introduced a new OPNET product for optical network design.

The formation of the joint venture, initially announced in March of this year, brings together two leaders in their respective fields. Comsof's core competencies are in advanced algorithms for designing optical networks. Collectively, members of Comsof have authored more than 86 publications related to optical networking. OPNET has a 15 year track record for developing and delivering advanced software solutions to the world's top service providers, network equipment manufacturers, and enterprises.

Together they are collaborating to deliver advanced solutions that enable service providers to better plan, design, and evaluate optical networks. The joint venture, WDM NetDesign B.V.B.A, based in Ghent Belgium, has ownership of the intellectual property and key staff associated with the Comsof's WDMNetDesign product. The joint venture will focus on research and development of optical network design software to be used in OPNET's products, including Netbiz, SP Guru, and the new WDM Guru.

WDM Guru, to be unveiled at OPNETWORK 2001, is a new OPNET application that contains a superset of features from the WDMNetDesign product originally developed by Comsof. WDM Guru will support both mesh and ring transport networks, and will address topological design, routing, network dimensioning, grooming, and availability analysis. OPNET assumes primary responsibility for sales and marketing of the new product.

The joint venture underscores OPNET's commitment to addressing the planning and operational needs of today's service providers. In making today's announcement, OPNET Technologies' President and CTO, Alain Cohen, stated, "Comsof has contributed significant intellectual property that augments our existing products' capabilities at the optical transport layer, an area where precise planning can lead to substantial savings for providers of high-bandwidth services."

WDM Guru will be presented during several sessions at OPNETWORK 2001, the world's largest event on network design, modeling, and management. OPNETWORK 2001, August 27th - 31st at the Reagan Center in Washington DC, also features presentations on optical networking from prominent speakers including:

• Prof. Dimitri Bertsekas of the Massachusetts Institute of Technology Routing Algorithms: From Packet Networks to All-Optical Networks
• Dr. Subir Biswas of Tellium StarNet Modeler: A Hybrid Modeling System for Restoration in Optical Networks
• Prof. Raj Jain of Nayna Networks and Ohio State University Optical Networks: Recent Advances, Trends, and Issues
• Don Stalter and Dr. Siddhartha Devadhar of Terawave Communications Modeling and Planning for New Telecom Technologies

About OPNET Technologies, Inc.
Founded in 1986, OPNET Technologies, Inc. is the leading provider of intelligent network management software. The OPNET product suite combines predictive modeling and a comprehensive understanding of networking technologies to enable its customers to more effectively design and deploy networks, provision services, diagnose network and application performance problems, and predict the impact of network changes. For more information about OPNET and its products, visit www.opnet.com.

About Comsof
Located in Belgium, one of the network nerve centres of Europe, Comsof is a leading provider of easy-to-use network design, planning and evaluation software for telecom network suppliers and operators. The company's core strengths include WDM transport networks, metropolitan networks and access network design. Comsof uses its in-depth technical experience with transport and access networks to deliver both software solutions and consulting services for present and future telecom network suppliers and operators.

Safe Harbour Statement
The statements contained in this press release that are not purely historical are forward-looking statements within the meaning the Private Securities Litigation Reform Act of 1995, as amended, including statements regarding OPNET Technologies Inc.'s expectations, beliefs, intentions, or strategies regarding the future. All forward-looking statements included in this document are based upon information available to OPNET Technologies, Inc. as of the date hereof; OPNET Technologies, Inc. assumes no obligation to update any such forward-looking statements. Forward-looking statements involve risks and uncertainties, which could cause actual results to differ materially from those projected. For a discussion of such risks and uncertainties, see the Company's reports filed with the Securities & Exchange Commission, including its 10-Q for the quarter ended June 30, 2001.

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Note to editors: The word OPNET is spelled with all upper-case letters.

OPNET Media Contact:
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OPNET Technologies, Inc.
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