Spirent Targets Metro Edge Networks with New Test Unit; SmartBits BRTU Helps Service Providers with Service Quality.

Business Editors/High-Tech Writers

ROCKVILLE, Md.--(BUSINESS WIRE)--March 23, 2004

Spirent Communications' new SmartBits Broadband Remote Test Unit (BRTU) unveiled today will help service providers better test their metro optical networks and the high-speed data services they provide to enterprise customers.

A rack-mounted and compact test unit, the SmartBits BRTU supports the next generation of add drop multiplexers and multi-service provisioning platform devices offered by such companies as Ciena, Lucent and Nortel and now being deployed by service providers in their metro networks.

"Service providers continue to make significant investments in their metro networks to support the growing demand from their largest business and government customers for high-speed data services," said David Rennyson, vice president of marketing for Spirent Communications. "The SmartBits BRTU allows service providers to test a range of data services to identify and fix any performance issues quickly, ultimately leading to higher customer satisfaction levels."

Spirent's SmartBits BRTU enables service providers to verify network performance at the physical and logical layers and correlate events across the layers -- all from a single connection. For example, Spirent's new unit can test a range of services from traditional private lines to high-speed DS-3 and OC-3 connections as well as frame relay and ATM networking applications. In addition, service providers using SmartBits BRTU won't have to purchase new testing hardware when they begin introducing OC-48 and other new services. The SmartBits BRTU can easily be loaded with new software to accommodate emerging technologies.

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

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