RADVISION Announces New H.323 Toolkit v4.2, Supporting Advanced Features Found in Latest ITU-T H.323 Standards.

Business Editors/High-Tech Writers

GLEN ROCK, N.J.--(BUSINESS WIRE)--Dec. 11, 2003

Call Privacy, Encryption and Denial of Service Protection

Now Supported

RADVISION (Nasdaq:RVSN), the industry leader in providing a wide range of development solutions for voice, video, and data collaboration over IP and 3G, today announced the general availability of its new H.323 Protocol Toolkit version 4.2. This toolkit is the latest release of the company's award-winning H.323 toolkit and supports new features specified in version four of the ITU-T H.323 standard and additional specs ratified. The RADVISION H.323 Protocol Toolkit is available on many operating systems including multiple MS-Windows platforms, UNIX operating systems, and most real-time operating systems (RTOS) such as VxWorks, Nucleus, WinCE and Texas Instruments DSP BIOS.

As the leading industry provider of H.323 technology, RADVISION offers the widest range of development tools for creating and testing H.323-based products and services. In addition to supporting the latest enhancements in ITU-T H.323 standards, the toolkit also boasts a number of additional features requested by RADVISION customers, enabling them to develop new cutting-edge communications products or upgrade their existing product lines with new functionality.

"We are continuing to track and actively participate in the various standards bodies, giving us the edge in upgrading our toolkits to support the latest version of voice, video and data collaboration standards -- whether SIP, H.323, MEGACO, MGCP or 3G-324M for 3G video telephony," said Eli Orr, H.323 Product Manager for RADVISION's Technology Business Unit. "By delivering the most advanced and mature tools for H.323, we enable our customers to get a leap on the competition by developing market-leading product offerings."

IPv6/IPv4 support (Windows, Solaris, Linux)

The RADVISION H.323 Protocol Toolkit v4.2 supports the development of products supporting both IPv4 and IPv6 protocols. This is significant as many service providers are looking for products that both support services running on the new IPv6 schema while still offering backwards compatibility with today's IPv4 schema.

Latest ITU-T Call Control H.245 Version 10 Support

H.323 uses H.245 as the call control protocol, for capability exchange between communicating terminals as well as media channels creation and termination. This functionality, which is similar to the use of SDP in SIP-based communication, enables communicating devices to establish multimedia channels based on common capabilities.

What differentiates H.245 from SDP is its support of multi-party session operation for voice, video, and data collaboration between multiple end points. These include support of a high ranked terminal (called Chair Control) that can control others and also the sharing of voice, video, and data channels between multiple parties during a conference.

The new RADVISION H.323 Protocol Toolkit v4.2 features version 10 of the H.245, ratified on July 2003. The new version adds support for the useful dual-video feature, enabling endpoints to switch dynamically during a session between camera and another resource such as Power Point presentation or a video clip.

Enhanced H.235 support for Scalable Authentication and Media Privacy

Scalable and well-defined authentication, as well as media streams encryption, is an important issue for service providers and users. The new version of the RADVISION H.323 Protocol Toolkit supports, with an optional add-on H.235 module, advanced features defined in H.235 Annexes D, E, and F, covering scaleable digital signatures solutions and media encryption signaling. This includes robust PKI (Public Key Infrastructure)-based user authentication, using both certificates and digital signatures. The media privacy support enables users to create a call session with other peers and to encrypt the media, creating a powerful barrier to eavesdropping by a third party. Additionally an encryption key is generated between the communicating peers so that it will be almost impossible for third parties to decrypt the signal.

Denial of Service (DOS) Protection

Version 4.2 of the H.323 Protocol Toolkit also adds increased protection against DOS attacks, which attempt to cause buffer overrun scenarios that can lead to server failure. The RADVISION H.323 Protocol Toolkit v4.2 enables its customers to develop solutions that recognize DOS attacks and implement safeguards to maintain system integrity.

Support of Full Suite of ITU-T H.450 Supplementary Services

RADVISION H.323 v4.1 toolkit already supports the entire supplementary suite of H.450.1-12, with services such as call transfer, hold, forward, park and pick-up, call intrusion and more. Based on usage feedback, RADVISION enhanced its new H.323 Protocol Toolkit v4.2 to offer improved H.450 callback and control services operating with various supplementary services. This feature enables developers to improve management of call flows within an H.323 solution (e.g., tracking state transitions and adding differentiated capabilities).

Various Additional Toolkit Enhancements

The entire RADVISION suite of developer toolkits, including those for the H.323 protocol, not only deliver functionality and underlying code that supports the evolving communications standards but also delivers powerful development features that enable the creation of advance, feature-rich solutions that continue to push the envelope in packet-based communications solutions.

Over the course of the company's strong relationships with equipment developers, the company has implemented a large number of toolkit API enhancements, significantly aiding in next generation product development. The latest release of the company's H.323 Protocol Toolkit v4.2 is no exception and features a number of new developer-requested enhancements such as improved APIs for enhanced call control, better configurations, and even more robust callback functionality.

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 Web site 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 10-K 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.