Spirent Communications and Verizon Wireless Collaborate Toward End-User Satisfaction; Spirent's APEX C2K Automates 3G Applications Evaluation.

Business Editors

ROCKVILLE, Md.--(BUSINESS WIRE)--June 3, 2004

Spirent Communications(TM) (NYSE:SPM)(LSE:SPT) today announced that Verizon Wireless has selected its APEX C2K Applications Performance Test Platform to verify the performance and reliability of resident and downloadable software applications for 3G wireless handsets.

"As part of Verizon Wireless' stringent handset-testing process, Spirent's APEX C2K platform has made the evaluation cycle shorter and increased the thoroughness of our testing of advanced applications and features," said Lou LaMedica, executive director - CPE evaluation and development at Verizon Wireless. "With the number and complexity of our 3G applications constantly increasing, it's critical that we ensure the handsets we approve for our network can smoothly deliver these advanced features and applications to Verizon Wireless customers."

"Working with Verizon Wireless has allowed Spirent to ensure that the APEX C2K accurately reflects the needs of wireless customers," states Rob VanBrunt, vice president of wireless product marketing for Spirent Communications. "Verizon Wireless' feedback has allowed us to design a platform powerful enough to automate performance testing for the latest wireless data applications, yet flexible enough to grow as new test requirements evolve."

CDMA handset testing is evolving from minimum performance and interoperability testing to more advanced application performance and end-user experience testing. Spirent's APEX C2K platform is a scalable test solution designed to meet the evolving needs of wireless application development. Spirent is targeting the system's advanced automation to address a key weakness in existing test methodologies: Up to now, testing of CDMA2000 1X features, such as Mobile IP, has largely been a manual, time-consuming process. While solutions exist to perform some elements of application and feature testing, APEX C2K is the first integrated platform to automate this analysis. This automation allows for a large number of test cases to be run in a relatively short time, reducing the amount of valuable engineering resource dedicated to test strategy execution.

For more information on APEX C2K, contact Mike Keeley at [phone] or via e-mail at [e-mail]. The APEX C2K CDMA Applications Performance Test Platform is available immediately.

Spirent Communications' wireless test solutions aid in all phases of mobile handset development and deployment for the world's leading chipset, handset and infrastructure manufacturers and mobile service providers. Spirent is 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 leveraged its success in mobile performance and certification testing in the CDMA market to also bring comprehensive performance analysis to the GSM and WCDMA 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

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

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