Java SIP Toolkit 2 Enables Faster and Simplified Development of Advanced Telecom Applications

FAIR LAWN, New Jersey, April 10, 2006 — RADVISION (Nasdaq:RVSN), a leading provider of multimedia conferencing and communications platforms, today announced the release and immediate availability of a Java version of its award-winning session initiation protocol (SIP) toolkit for real-time communication applications, such as voice over IP (VoIP) and instant messaging (IM). The new toolkit significantly shortens development cycles thereby enabling even faster time-to-market for a variety of new and innovative services.

"The release of the Java version underscores RADVISIONâ_Ts position as the leading developer of SIP toolkits and is highly supportive of the ongoing migration of telecommunications towards Internet Protocol (IP) using SIP technology," said Adi Paz, Senior Director of Product Management and Marketing for RADVISIONâ_Ts Technology Business Unit. "Many of our customers have been expressing the need for a Java SIP toolkit, and we are pleased to meet their growing requirements."

Java programming language, which is rapidly gaining popularity among developers, can be used to write software on one platform and run it on another, create programs that run within web browsers, develop server-side applications, and write applications for cell phones and other consumer communication devices. Java SIP is a fundamental building block for web-based endpoint-oriented communication applications.

The Java SIP Toolkit can be used to develop click-to-talk applications, as well as a variety of applications for web call centers, and soft phones for laptops and PDAs. It also can be used as a major building block for innovative and time-critical advanced telecom services on the server-side such as: least-cost call routing, smart call diversions based on user preferences, smart conferencing, as well as for transforming text messages to voice playback.

Similar to all of RADVISIONâ_Ts SIP toolkits, the Java SIP toolkit addresses carrier-side applications for soft switches and application servers. The Java SIP Toolkit supports operator-grade loading of busy hour call attempts (BHCAs) and has enhanced carrier-grade features, including advanced SIP signaling functionality. The small footprint allows efficient operation in SIP terminals and IP handsets, as well as network-side implementations. In addition, Java SIP is considered to be the ideal advanced technology for service delivery platforms (SDPs).

The Java SIP toolkit complies with the latest version of the JSR32 standard, version 1.2, of which RADVISION is an active contributor.

Considered an industry-leading solution, RADVISIONâ_Ts award-winning SIP product portfolio and the Java SIP Toolkit provide multiple application program interface (API) layers for optimal control and flexibility when used to develop new products and services. Designed from the ground up to be robust, highly versatile development tools, the toolkits simplify development of communications systems and devices based on Internet Engineering Task Force (IETF) SIP.

About RADVISION

RADVISION LTD. (Nasdaq: RVSN) is the industryâ_Ts 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 RADVISIONâ_Ts filings with the Securities Exchange Commission, including RADVISIONâ_Ts 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.