Spirent Extends its Leadership in Push-to-Talk Handset Test; First Commercial Solution for Lab-based Evaluation of Handset Performance.

ROCKVILLE, Md. -- Spirent Communications(TM) (NYSE:SPM) (LSE:SPT) announced the commercial availability of APEX C2K: PoC, the first lab-based solution for evaluating performance of Push-to-Talk over Cellular (PoC) handsets for CDMA networks.

CDMA carriers looking to maximize return on their deployment investment have turned to data-oriented services such as PoC to help increase average-revenue-per-user (ARPU) and reduce churn. However, the commercial success of PoC will ultimately be determined by end-user satisfaction with the services it enables. Subscribers expect the end-user experience to compare favorably to existing analogous services, such as CDMA circuit-switched voice and existing PoC implementations. Some recent PoC deployments have slowed once initial rapid subscriber adoption helped identify performance issues.

"The end-user experience is going to be vital to the ultimate success of PoC services," said Denis Ledgerwood, PoC product manager at Spirent Communications' Wireless division. "Customers expect the service itself to be robust, with delays comparable to existing PoC implementations and speech quality that compares well with familiar circuit-switched speech. The major CDMA carriers have chosen a Voice over IP (VoIP) implementation. VoIP can introduce new speech quality issues which need to be understood and their impact minimized. Trying to quantify PoC performance in all these areas using traditional field testing is unreliable, incomplete and extremely time-consuming. The logical approach to quantifying PoC handset performance and its impact on the end-user experience is to bring testing into the lab. This allows a controllable environment to be established, configurable and repeatable test cases to be executed and the total test time to be dramatically reduced."

Spirent's APEX C2K: PoC Application Performance Test System is an automated lab-based performance and protocol analysis system designed to quantify the performance of VoIP PoC handsets. APEX C2K: PoC has been designed to bring PoC handset testing into the lab, where issues are more readily identified and more quickly resolved. The system is built upon APEX C2K, Spirent's industry-leading CDMA Applications Performance Test Platform. APEX: PoC includes both performance and protocol test cases. Performance test cases establish key timing metrics, including call-setup and inter-call latency performance, along with voice quality and audio delay performance. Protocol test cases focus on interoperability with the PoC Control Server and other network resources that impact the robustness of PoC services.

For more information on APEX C2K: PoC, contact Denis Ledgerwood at [phone] or via e-mail at [e-mail]. APEX C2K: PoC is available immediately.

Spirent's wireless test solutions aid in all phases of mobile device development and deployment for the world's leading chipset, mobile and infrastructure manufacturers and mobile network operators. Spirent's extensive CDMA experience has led to it being considered by the industry the "one-stop-shop" for CDMA handset performance and certification testing. Among its accomplishments, Spirent has introduced the first and only integrated solution available to test location-capable CDMA phones, a critical element of assisting manufacturers in meeting the U.S. FCC E911 requirements. Spirent has now leveraged its success in mobile performance and certification testing to bring comprehensive performance analysis to the W-CDMA market.

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 2003 revenue of $394 million and has 1,800 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

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