Spirent® Communications Provides GENBAND Powerful IP Telephony Performance Test Solution

Business Wire, Sept 25, 2006

Abacus 5000 Allows Thorough Testing and Evaluation of Signaling Gateways and Softswitches

SUNNYVALE, Calif. -- Spirent Communications (NYSE:SPM) (LSE:SPT), a global provider of performance analysis and service management solutions, announced today that GENBAND has chosen Spirent's Abacus 5000 as one of its primary IP Telephony performance assessment tools. GENBAND is a leading provider of IMS-based telecommunications applications and infrastructure products. Spirent's Abacus platform gives GENBAND a wide set of testing capabilities combined with a superior technical support team. With its best-of-breed solutions, Spirent removes the complexity and worries of testing, giving its customers the freedom to focus on design and development. By partnering with Spirent, GENBAND will be able to enhance their development productivity by:

* Reduced test time with multi-user environments

* Experienced and responsive client services that enable effective test methodologies

* Comprehensive test capabilities that span feature development, system test and customer engineering

"We pride ourselves on offering reliable products to enable our customers' success," said Don Dill, Senior Director, Software Development, GENBAND. "By working with Spirent Communications products and support team we are able to ensure that our IP-based products and solutions are evaluated in the most thorough and timely manner possible."

"Spirent is committed to working with customers like GENBAND to further the success of next-generation IP Telephony applications," said Bahaa Moukadam, vice president of next-generation networks for Spirent Communications. "The capacity and functionality provided by the Spirent Abacus platform enables thorough testing of scalability, performance, interoperability and quality for IP Telephony applications. This broad range of capability allows customers to focus on development and leave the test methodology to us."

The Abacus 5000 allows softswitch and signaling gateway vendors to assess the performance of their equipment in an environment similar to a real network, one where QoS and security are enabled while operating at extreme loads. This significantly reduces the time it takes to identify faults and reduces the risk of faults being revealed in turn-up testing by a customer validation lab. Spirent Communications' Global Services team provides support and education services focused on helping customers meet their complex testing and evaluation requirements.

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 Communications' solutions are used by more than 1,700 customers in 30 countries, including the world's largest equipment manufacturers, service providers, enterprises and governments. Based in Sunnyvale, CA, Spirent Communications has 1,800 employees worldwide. Spirent Communications plc Ordinary shares are traded on the London Stock Exchange (ticker: SPT) and on the New York Stock Exchange (ticker: SPM; CUSIP number: 84856M209) in the form of American Depositary Shares (ADS), represented by American Depositary Receipts, with one ADS representing four Ordinary shares. Spirent Communications' sales to the United States government are made through Spirent Federal Systems Inc. www.spirentfederal.com

About GENBAND

GENBAND is the leading supplier of IP multimedia application and infrastructure products and solutions for a diverse set of VoIP and IMS networks worldwide. These IMS-ready applications and solutions enable wireline, cable, and wireless service providers to rapidly deploy new multimedia services, while providing a foundation to transition legacy networks to next generation networks. GENBAND has deployed its IP Multimedia products and technology to over 100 customers with more than 750 deployments, across three continents. Headquartered in Plano, Texas, GENBAND has research and development facilities in Fremont, California; Austin and Plano, Texas; and New Delhi, India. Additional information is available at www.genband.com.

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