RADVISION Chairs Leading Industry IMS Interoperability Group.

The IMTC IMS Activity Group Focuses on Industry-Wide Interoperability of Terminal-Network Signaling and Media

TEL AVIV, Israel -- RADVISION (Nasdaq: RVSN), a leading provider of video network infrastructure and developer tools for unified visual communications over IP, 3G, and emerging next-generation IMS networks, announced today a new activity group has been formed by the International Multimedia Telecommunications Consortium (IMTC) dealing with interoperability issues related to the IP Multimedia Subsystem (IMS). The activity group currently includes among its members representatives from leading companies in the telecommunications industry, such as Ericsson, Motorola, NMS Communications, Nokia Corporation, Samsung Electronics, Sharp Corporation and Sony Ericsson Mobile Communications. Tsahi Levent-Levi, a Product Manager in RADVISION's Technology Business Unit, was chosen to chair the activity group. IMTC has been involved for over a decade in interoperability testing and has been a driving force in the adoption and deployment of mature H.323 and 3G-324M devices and networks.

The IMTC IMS activity group promotes and facilitates the development and implementation of interoperable multimedia conferencing solutions based on open international standards, as well as other standards organizations. The proliferation of open standard solutions will advance the multimedia conferencing industry and further its widespread deployment. In order to do this, the IMTC IMS activity group focuses on interoperability of end-to-end functionality and terminal-network signaling and media. In addition, the IMS activity group finalizes IMS client application specifications, creates test specification and implementation guides, and organizes test events. This includes performing and documenting well-planned and controlled interoperability tests, as well as planning, executing, and tracking rigorous interoperability tests for the benefit of participating member companies. The activity group reports feedback to 3GPP, 3GPP2, GSMA and other standard developing organizations to apply the knowledge gained through testing to improve relevant standards.

The IMTC IMS activity group also allows competing companies to conduct regular dialogue regarding interoperability of their products and to develop a common stance enabling them to help shape and evolve industry-wide standards.

The Evolution to IMS

The IP Multimedia Subsystem (IMS) is a standardized Next Generation Networking (NGN) architecture that meets an important need in the growing trend towards fixed, wireless and mobile network convergence. The IMS core network enables operators and service providers to deliver identical IP services to both fixed and mobile customers over any access. As IMS is the cornerstone of converged telecommunications, it offers unique opportunities for the development of next-generation devices and equipment and converged mobile communications. RADVISION is leading the IMS evolution with the RADVISION IMS Express[TM], a complete IMS Developer Suite. These IMS developer tools and IMS-ready infrastructure products provide all the necessary protocol toolkits, IMS application servers, IMS testing tools, and an IMS client package for terminal developers - complete with application engines in addition to the underlying signaling and media technology.

"RADVISION has always placed interoperability as a top priority, in the belief that this will serve to advance the industry and bring about innovation," said Adi Paz. "The advent of IMS underscores the importance of interoperability across all spheres. Our chairing this Activity Group enhances the quality of our IMS Developer Suite significantly."

About RADVISION

RADVISION (Nasdaq: RVSN) is the industry's leading provider of market-proven products and technologies for unified visual communications over IP and 3G networks. With its complete set of standards-based video networking infrastructure and developer toolkits for voice, video, data and wireless communications, RADVISION is driving the unified communications evolution by combining the power of video, voice, data and wireless - for high definition video conferencing systems, innovative converged mobile services, and highly scalable video-enabled desktop platforms on IP, 3G and emerging next-generation IMS networks. For more information about RADVISION, visit www.radvision.com.

This press release contains forward-looking statements that are subject to risks and uncertainties. Factors that could cause actual results to differ materially from these forward-looking statements include, but are not limited to, general business conditions in the industry, changes in demand for products, the timing and amount or cancellation of orders and other risks detailed from time to time in RADVISION's filings with the Securities Exchange Commission, including RADVISION's Form 20-F Annual Report. These documents contain and identify other important factors that could cause actual results to differ materially from those contained in our projections or forward-looking statements. Stockholders and other readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date on which they are made. We undertake no obligation to update publicly or revise any forward-looking statement.

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