Spirent Communications Introduces Network Edition 6.1 Software Featuring PPPoE Testing Capabilities.

Business Editors/High-Tech Writers

ROCKVILLE, Md.--(BUSINESS WIRE)--Dec. 9, 2003

New software release for Avalanche(TM) generates traffic equivalent of

64,000 households, enabling broadband access providers to simulate a

mid-sized city from a single test appliance

Spirent Communications(TM) (NYSE:SPM)(LSE:SPT) today announced it has developed a new test solution that will enable scalable realistic testing of broadband access technologies, furthering the company's top-level initiative to deliver innovative integrated layers 2-7 testing solutions to telecom service providers worldwide.

Spirent's Network Edition 6.1 software for its Avalanche(TM) product line enables equipment manufacturers and service providers serving the growing broadband access market to effectively test real application traffic running over Point-to-Point Protocol over Ethernet (PPPoE). With this new solution, users can effectively test Video on Demand (VoD), bandwidth on demand, premium services and differentiated service offerings from an end-user perspective.

The broadband access market continues to grow at a rapid pace, fueled by households using DSL service for home office and telecommuting needs. This type of use, along with the varied applications being run over DSL today, demand that enterprises and service providers deliver on a high level of end-user satisfaction. The new capabilities in Network Edition 6.1 enable providers to more comprehensively test their services prior to deployment in order to help guarantee a higher quality of service to consumers.

"Network Edition 6.1 software makes it even easier for service providers to test the latest in broadband access technologies," said Roy Chua, director of product marketing for Spirent Communications. "Central to Spirent's integrated testing strategy is to build testing solutions from the end-user viewpoint. With the release of Avalanche Network Edition 6.1, service providers rolling out value-added services like bandwidth-on-demand and video-on-demand will be able to better understand how applications are running over their networks and provide their end customers with a superior quality of service."

The PPPoE testing feature in Network Edition 6.1 software offers high rates of PPP session setups, large user handling capabilities, configuration for multiple types of common authentication and the ability to simulate multiple classes of users and measure the quality of their user experience as defined by application-specific metrics. Furthermore, the wide breadth of Avalanche application protocols continue to be supported over PPPoE, including web browsing, video streaming, file transfer and e-mail access.

Network Edition 6.1 software for the Avalanche product line will be available within 30 days.

About Spirent's Avalanche Product Line

Avalanche is designed for network equipment manufacturers, service providers and Web site managers that demand absolute realism and control under all conditions. Avalanche challenges any computing infrastructure's ability to stand up to the load and complexity of the real world. Avalanche can generate in excess of 50,000 HTTP requests per second, and supports HTTP/1.0, HTTP/1.1, HTTPS, RTSP/RTP (Apple QuickTime(R)), RealSystem(R) streaming, Microsoft(R) Windows Media(R) 8 and 9 Series, SMTP, POP3, DNS, Telnet and FTP. In addition, Avalanche can generate Distributed Denial of Service attack traffic inline with any mix of multi-protocol traffic. Through clustering, Avalanche can scale to the needs of even the world's largest infrastructures. Many leading corporations use Avalanche to ensure that their products and services excel in real-world conditions. Real-world conditions are accurately replicated by simulating error conditions, realistic user behavior, and maintaining over one million open connections from distinct IP addresses. Current customers include AT&T, BEA, Cable & Wireless, Cisco Systems, CNET, Deutsche Bank, eBay, Extreme Networks, F5 Networks, Forbes.com, Foundry Networks, Intuit, MSNBC, Network Appliance, NetScreen, Nortel Networks, NTT DATA, SBC Communications, and WatchGuard. http://www.spirentcom.com/avalanche.

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 2002 revenue of $476 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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