Spirent(R) Communications Launches Data Throughput Tester for HSDPA User Equipment; Coincides with Roll Out of First Ultra High-Speed Mobile Networks.

ROCKVILLE, Md. -- Spirent Communications (NYSE:SPM) (LSE:SPT), announced the latest member of its WCDMA testing solution family of products. Spirent's User Equipment (UE) Performance Tester is designed to accelerate the successful deployment of next generation, high-speed wireless technology. Spirent is a worldwide provider of integrated performance analysis and service assurance systems for next-generation network technologies.

For these deployments to succeed, handset manufacturers, network operators, and test houses must undertake extensive handset performance testing. Spirent's UE Performance Tester offers a complete platform to evaluate all aspects of data throughput for HSDPA and R99, from the physical layer to the application layer. The platform can emulate complex wideband radio channel characteristics so that data throughput can be credibly assessed under realistic RF conditions and carriers can gain a realistic view of how they will perform on the live network. It offers network operators and device manufacturers a new and effective way to evaluate wireless devices in terms of data throughput efficiency and the user experience, which heavily affects both customer satisfaction and the efficient use of network resources.

"Our customers' success is dependent upon how well they deliver high-speed data services to their customers," said Rob VanBrunt, vice-president of product marketing at Spirent Communications. "The very nature of HSDPA's shared data pipe increases the complexity of the interactions between the network and the User Equipment. Thorough performance testing ensures flawless delivery of these data services from day one."

The UE Performance Tester platform configuration consists of Spirent's market leading AirAccess WCDMA-HS Network Emulator, the SR5500 Wireless Channel Emulator, Test Drive software and the Data Throughput Test Pack. The AirAccess WCDMA-HS provides comprehensive network emulation that includes the Core Network, RNC, NodeB and Cell. The SR5500 generates accurate and repeatable impairments to determine device performance in realistic RF environments. Test Drive software is executive software that makes it easy to automate unattended test sessions. The Data Throughput Test Pack is a software module that implements data throughput testing.

The launch of UEPT comes as the majority of mobile operators prepare to deploy HSDPA networks. HSDPA data cards are now commercially available, and handsets will arrive soon. Prototype devices capable of even higher data rates are in the process of being developed. The UE Performance Tester architecture meets today's challenges and supports the evolution of WCDMA technology in the future.

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 or registered trademarks of Spirent plc. All other trademarks or registered trademarks mentioned herein are held by their respective companies. All rights reserved.

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