Spirent Enables Robust EV-DO Services; APEX C2K:SC Ensures Reliable EV-DO Application Performance.

NEW ORLEANS -- Spirent Communications(TM) (NYSE:SPM)(LSE:SPT), a global leader in wireless mobile device performance testing, announces the availability of its APEX C2K:SC platform for automated testing of EV-DO applications.

Although Asia boasted the first commercial EV-DO applications, 2004 saw the launch of nine new EV-DO networks around the world. Deployment of another 17 networks is underway for 2005. EV-DO is now live on five continents, having taken advantage of the 450 MHz band (CDMA450) to accelerate the transition from 1G to 3G networks and the 2.1 GHz band to provide high-speed packet data services to new markets. EV-DO is no longer an experiment but a proven, robust and high revenue-generating technology.

The data rates and services offered by EV-DO have led to an explosion of deployments and subscribers (almost 10M as of September 2004). As the user base grows, so does the need to reliably test EV-DO applications to ensure end-user satisfaction with EV-DO capable devices and the new services they support. Signaling Conformance testing ensures users can successfully interoperate with an EV-DO network and roam across EV-DO networks from different service providers and infrastructure manufacturers.

Spirent's APEX C2K:SC provides a proven platform to reliably perform Signaling Conformance testing on EV-DO capable mobile devices and to verify the robustness of EV-DO subscriber applications. APEX C2K:SC automates test cases from TIA-919 (3GPP2 C.S0038), the Signaling Conformance standard for CDMA2000 High Rate Packet Data Air Interface. APEX C2K:SC is a fully integrated system, built upon Spirent's industry-leading APEX test platform for automated application testing.

"2005 is clearly an important year for EV-DO growth," said Rob VanBrunt, vice president of product marketing at Spirent Communications. "At Spirent, we continually strive to enable our customers to bring their products to market faster, with better performance. With the APEX C2K:SC solution, our customers are able to ensure that their new EV-DO devices and services will be delivered with robust, reliable performance."

APEX C2K:SC includes TestDrive SC Automation Test Executive software, UDM Universal Diagnostic Monitor software for control and monitoring of the EV-DO device under test, and AirAccess 1xPLUS 1X and EV-DO Network Emulation.

Spirent's wireless test solutions aid in all phases of mobile device and wireless network development and deployment for the world's manufacturers and mobile network operators. Spirent's extensive experience in wireless protocols has led to it being considered the "one-stop-shop" for CDMA handset performance and certification testing. Spirent has leveraged its success in mobile performance and certification testing to bring comprehensive performance analysis to the W-CDMA market. The company's wireless core infrastructure GPRS and CDMA performance test systems help service providers identify performance ceilings, enable vendor selections and plan network capacity prior to deployment, to facilitate smooth service delivery.

Spirent has helped accelerate wireless service delivery by introducing the first and only solutions to test CDMA, WCDMA and GSM location-capable mobile devices. These systems play a critical role in assisting the validation of emergency services such as the U.S. FCC E911, and in facilitating the roll-out of commercial location-based services.

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, Md., 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 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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