Participation in the IMS Forum PlugFest II is Further Testimony to RADVISIONâ??s Commitment to IMS Interoperability

TEL AVIV (June 21, 2007) –

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, today announced that it tested several IMS products at the IMS Forum’s IMS Plugfest(TM) II interoperability test event held June 4 through 8 at the University of New Hampshire InterOperability Lab in Durham, NH. RADVISION is an active member of the IMS Forum, the industry’s only Forum dedicated to the acceleration of IP Multimedia Subsystem (IMS) application and service interoperability, in addition to chairing an IMS Activity Group for IMS client IOT.
“RADVISION’s IMS SIP Toolkit, IMS DIAMETER Toolkit, and ProLab(TM) IMS Testing Suite were an instrumental part of the IMS Forum Plugfest,” reports Adi Paz, Senior Director of Product Management and Marketing for RADVISION’s Technology Business Unit. “RADVISION’s IMS Express(TM), the complete IMS Development Suite includes these products and more, and offers the most complete suite of IMS-compliant development tools available in the market. RADVISION places special emphasis on IOT, especially in the area of IMS as it emerges to become an industry standard. This is why RADVISION considers the IMS Forum’s Plugfest to be one of the most important events in the field of IMS, and is honored to participate and help vendors achieve new levels of interoperability.”
RADVISION’s IMS Express, the complete IMS Development Suite includes all the necessary signaling and media protocols to easily and cost-effectively meet the IMS challenge.

* IMS SIP Toolkit
* IMS MEGACO/H.248 Toolkit
* IMS DIAMETER Toolkit
* IMS Advanced-RTP/RTCP Toolkit
* IMS Client Suite
* ProLab(TM) IMS Test Solution
* IMS SIP Server Platform

IMS Plugfest II is the second in a series of open testing events that are designed to foster interoperability by establishing an industry-recognized Interoperability certification for IMS services and applications. The Plugfest testing events are creating industry-recognized interoperability test plans for IMS applications and services, allowing service providers to expedite IMS service rollout.
The first Plugfest focused on interoperability of the IMS transport layer. Building on Plugfest I, the second Plugfest event, or Plugfest II, tests interoperability for VoIP, IP Centrex, SMS and Fixed-Mobile Convergence functionality.
“RADVISION has contributed to the planning and execution of our Plugfest interoperability events,” said Michael Khalilian, Chairman and President of the IMS Forum. “Protocol stacks are an essential part of the success of the IMS ecosystem. We are pleased to see RADVISION taking part in the IMS Plugfest.”

About RADVISION

RADVISION (NASDAQ: RVSN) is the industry’s leading provider of market-proven products and technologies for unified visual communications over IP, 3G and IMS 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 http://www.radvision.com/

About the IMS Forum:

The IMS Forum® is a global, non-profit industry association devoted to interoperable IP Multimedia Subsystems services and solutions. IMS Forum’s mission is to accelerate the interoperability of IMS applications and services, enabling enterprise and residential consumers to quickly benefit from the delivery of quadruple play voice, video, internet and mobile services over broadband via cable, wireless and fixed networks. The IMS Forum is the creator and organizer of the IMS Plugfest(TM), the industry’s only event focused on IMS services interoperability verification and certificationThrough its organized Plugfests, working group interaction, and other activities, forum members are able to develop cost-effective technical frameworks for converged IP services over wireline, cable, 3G, WiFi and WiMAX networks. For additional information or to join the IMS Forum and the IMS Plugfests, please visit http://www.imsforum.org/

For Further Information contact:
Cathy N. Clarke
IMS Forum
617-527-2089
pr@imsforum.org

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.

Source: RADVISION