RADVISION Releases Version 2.5 of Its Industry-Leading SIP Server Platform.

FAIR LAWN, N.J. -- Version 2.5 of RADVISION's Award-Winning SIP Server Platform Offers to SIP Server Application Developers Extended Capabilities for Developing the Latest Feature-Rich Products

RADVISION (Nasdaq:RVSN) today announced the availability of Version 2.5 of the RADVISION Session Initiation Protocol (SIP) Server Platform. Immediately available to RADVISION customers around the world, the new release of the award-winning platform offers significantly broader capabilities--interfacing to external databases as well as enabling the development of presence servers and events packages.

Based on RADVISION's market proven SIP Toolkit, the new release is a powerful, standards compliant, and highly versatile set of development tools that provides fast time to market for SIP application development. "The enhanced SIP Server Platform allows our customers to realize significant competitive advantages," said Adi Paz, Sr. Director of Product Management and Marketing for RADVISION's Technology Business Unit, "because it simplifies the process of including new, value-added capabilities in SIP server applications."

Version 2.5 implements all of the necessary building blocks required for presence server and events package applications, as well as call establishment. These include the SUBSCRIBE/NOTIFY mechanism and presence message format, Winfo, PUBLISH, and XML encoding/decoding.

In many cases, the latest SIP servers need to interface to external databases, such as a security database or a location database. Version 2.5 of the RADVISION SIP Toolkit is enhanced with a Lightweight Directory Access Protocol (LDAP) client interface with H.350.4 schema (RFC 3944), as well as the ability to customize and build other schema for locating databases.

New features in Version 2.5 of the RADVISION SIP Toolkit include:

--LDAP client - an interface for external databases.

--PUBLISH handling - support for presence clients that publish their new presence state.

--Support for session timer RFC 4028 for 3G networks, which defines a way for the server to continually track an existing session.

--Support for general Uniform Resource Identifiers (URIs) including telephone, presence and instant messaging (IM).

--Numerous enhancements to existing features including Back-To-Back User Agent (B2BUA) client side, authentication, XML parser, application program interfaces (APIs), and more.

--High availability API - ability to store the state of an active SIP server and restore it on another SIP server.

Compliant with the latest IETF SIP specifications and key extensions, the RADVISION SIP Server Platform is a high performance SIP implementation and provides multiple API layers for optimal control and flexibility when developing innovative products and services. It is well suited for developing proxy servers, presence servers, general events servers, B2BUAs, registrars, redirect servers, soft switches, call session control functions (CSCFs), IP-PBX, and application servers (including conference servers, instant messaging chat rooms, third-party control servers).

Availability

Version 2.5 of the RADVISION SIP Server Platform is available immediately worldwide.

About RADVISION Software Development Products

RADVISION's award-winning protocol toolkits and platforms are the core technology containing rich sets of APIs to enable software engineers to simplify development of all types of VoIP applications and services. As the core technology for IP-based application development, the protocol toolkits and platforms are always up-to-date with the latest industry standards and thoroughly tested for interoperability with leading OEMs. Whether the application needs to support single or multiple protocols, RADVISION's developer products provide the most comprehensive suite of VoIP protocol stacks including SIP, MGCP, 3G-324M, H.323, MEGACO/H.248, RTP/RTCP, and RTSP.

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. Revenue from sales of RADVISION toolkits may have been recognized in prior quarters. 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.