Spirent Communications Introduces First VoIP Security Test Features on Award-Winning Platform.

SAN JOSE, Calif. -- H.235 VoIP Gateway Message Encryption Can Now Be Tested With Abacus 5000 IP Telephony Migration Test Platform

Spirent Communications(TM) today announced availability of the H.235 VoIP gateway message encryption test capability on its award-winning Abacus 5000 IP Telephony Migration Test System. Spirent Communications is a worldwide provider of performance analysis and service assurance systems for next-generation network technologies.

The H.235 capability of the Abacus 5000 enables network operators and equipment manufacturers to validate the effectiveness of signaling encryption for VoIP gateways and gatekeepers within a multi-zoned H.323 environment.

The H.235 support on the Abacus 5000 is the first in a series of IP telephony security implementations that Spirent is developing. The company plans to introduce a range of IP telephony security-specific test capabilities designed to target security challenges related not only to gateway signaling, but also to the media stream (Secure Real Time Protocol), the transport layer (Transport Layer Security), Encryption (IPSec) and protocol robustness testing.

"Deployment of high-performance IP telephony infrastructure will not happen if security weaknesses push the VoIP industry into a constant game of catch-up with hackers," said George Hamilton, senior analyst for The Yankee Group. "Development of security testing tools like this, early in the mass deployment curve, are a prerequisite to long term industry success."

Spirent is complementing its internal VoIP security research and development efforts through participation in the industry's first Voice over Internet Protocol (VoIP) Security Alliance. The VOIPSA (www.voipsa.org) was launched on February 7, 2005, by leading VoIP vendors, providers, security researchers and thought leaders, to discover and reduce VoIP security risks. Spirent is committed to VoIP security research projects and the development of tools and methodologies for public use and is chairing the Test working group for the organization.

"The convergence of voice and data networks opens new sets of security risks to network operators and users," said Bahaa Moukadam, vice president, IP Telephony, for Spirent Communications. "Consequently, Spirent considers IP telephony security testing an essential part of enabling and accelerating the migration to the converged network. As such, we will continue to bring to market innovative IP telephony security testing solutions to the benefit of our customers."

VoIP architectures employ gateways to carry traffic from one network to another. Call management servers instruct gateway controllers, or gatekeepers, through the Gatekeeper ReQuest (GRQ) messages to control multiple gateways. IP telephony equipment makers typically encrypt these signaling messages in compliance with the International Telecommunications Union's H.235 signaling encryption standard, a subset of the H.323 signaling standard. Spirent's Abacus IP Telephony testing platform now includes functional and load testing specific to GRQ messages and H.235 signaling encryption.

About Spirent Communications

Spirent Communications (www.spirentcom.com) is a global provider of integrated performance analysis and service assurance systems that enable the development and deployment of next-generation networking technology such as Internet Telephony, broadband services, 3G wireless, global navigation satellite systems, and network security equipment. Spirent's solutions are used by more than 1,500 customers in 30 countries, including the world's largest equipment manufacturers, service providers, enterprises and governments. Based in Rockville, Maryland, Spirent Communications reported 2004 revenue of $460 million and has 1,700 employees worldwide. The company is the largest business group of Spirent plc, traded on the London and New York Stock Exchanges (LSE: SPT; NYSE: SPM; CUSIP number: 84856M209). www.spirent.com. Spirent Communications' sales to the United States government are made through Spirent Federal Systems. www.spirentfederal.com

Spirent, Spirent Communications and the Spirent logo are trademarks of Spirent plc. All other trademarks or registered trademarks are held by their respective companies. All rights reserved.

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