Spirent Enables Comprehensive EV-DO Performance Testing; New Option Supports Automated Lab-based Analysis of EV-DO Terminal Performance.

ROCKVILLE, Md. -- Spirent Communications(TM) (LSE:SPT) (NYSE:SPM) announced the availability of a new EV-DO performance testing option for its market-leading APEX C2K CDMA Applications Performance Test Platform. The new APEX C2K EV-DO option adds EV-DO network emulation and test cases, giving CDMA carriers, handset manufacturers and test labs the ability to conduct fully-automated performance testing of 1xEV-DO terminals. With EV-DO already widely deployed in the Asia Pacific region and with North American deployment ramping up rapidly, user satisfaction with the performance of this broadband access technology and the services it enables is critical to its long-term success.

"With its higher data rates and the potential to support new applications such as broadcast video and multimedia, EV-DO offers significant new revenue opportunities for both CDMA carriers and equipment manufacturers," said Michael Keeley, market segment manager for CDMA technologies at Spirent Communications' wireless business. "Of course, the complex modulation schemes needed for higher data rates and the demands of new applications also present significant testing challenges. Until now there was no commercially available automated solution that enabled EV-DO terminals to be tested beyond conformance to industry standards or minimum performance requirements. Now Spirent offers a solution to that dilemma, helping to accelerate deployment of EV-DO and furthering Spirent's leadership in CDMA performance analysis."

Spirent's EV-DO Test Packs include automated test cases providing such statistics as data call set-up time, data transfer time, and data throughput rates. The system offers a lab-based means of analyzing terminal performance over time and under real-world scenarios, including propagation conditions and changing power levels. EV-DO Test Packs also enable automated Mobile IP testing, verifying a terminal's ability to interoperate and move within a Mobile IP-enabled network.

The EV-DO option is an upgrade to the Spirent Communications APEX C2K platform, a comprehensive CDMA performance test system which includes SR3452 CDMA Network Emulators, an SR5500 Wireless Channel Emulator and Spirent's APEX TestDrive Data Test Executive Software. The EV-DO option adds an SR3460 EV-DO Network Emulator to the system. APEX C2K is an expandable testing platform designed to grow along with the evolving testing needs of CDMA networks and equipment. Its advanced automation capability helps eliminate time-consuming manual features and application testing, accelerating the development of new products and enhancing the reliability of CDMA services.

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.

Spirent Communications, Spirent 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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