RADVISION Announces General Availability of the First Fully Compliant IMS SIP Protocol Toolkit; IMS SIP Toolkit Opens the Door to the Next Stage in the Evolution of Converged, Next Generation IMS Networks

Business Wire, July 17, 2006

FAIR LAWN, N.J. -- RADVISION (NASDAQ:RVSN), the leading provider of video network infrastructure and developer tools for unified visual communications over IP, 3G, and emerging next-generation networks, today announced the release and general availability of the industry's first IP Multimedia Subsystem (IMS) Session Initiation Protocol - SIP - Toolkit for real-time communication applications. Based on RADVISION's award-winning SIP toolkit, the IMS SIP Toolkit is a powerful and highly versatile set of tools that facilitates the development of IMS SIP applications while reducing development time and costs. The IMS-SIP toolkit is suitable for both clients and servers.

IMS is a SIP-based network that serves as the infrastructure for services and call or session control in advanced networks. IMS is the cornerstone for deploying truly converged advanced 3G networks, as well as additional types of networks, such as wireline telephony, packet cable, and WiMax. The IMS network entities that can be developed with RADVISION's IMS SIP Toolkit are P-CSCF, I-CSCF, S-CSCF, BGCF, AS, UE, MGCF, MRFC and SGW.

"With the release of IMS SIP toolkit, RADVISION is pioneering the deployment of next generation networks. This represents a major milestone in the migration toward IMS," said Adi Paz, Senior Director of Product Management and Marketing for RADVISION's Technology Business Unit. "The market has been waiting for the general availability of IMS products, and we are pleased to maintain our leadership role by being the first to market with our IMS Toolkit."

The IMS SIP toolkit is part of an entire family of products specifically designed for IMS networks. Additional products include the SIP Server, Java SIP, MEGACO, RTP Toolkits and the ProLab(TM) IMS Testing & Analysis suite.

Coded in ANSI C and cross-platform compatible, the IMS SIP Toolkit is available for all common operating systems. It features an open, object-oriented architecture, which makes it programmer-friendly and highly flexible. It provides multiple API layers and is inherently designed to offer both extensive functionality and complete flexibility. SIP extensions include support for IMS registration, MD5-AKA, RFC 3329 security agreement, IPsec with ESP transport mode and manual keying.

For further information on IMS, RADVISION has published a detailed IMS SIP white paper that can be downloaded from the company's website at: http://www.radvision.com/Resources/WhitePapers/ims_sip.htm.> About RADVISION

RADVISION LTD. (Nasdaq: RVSN) is the industry's leading provider of high quality, scalable and easy-to-use products and technologies for videoconferencing, video telephony, and the development of converged voice, video and data over IP and 3G networks. For more information please visit our website at 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.