Spirent Communications Provides Layer 2-7 Tests and Expertise to Enterprise Triple Play Test at the University of New Hampshire; UNH Lab White Paper Details Test Results of Converged, Enterprise-Scale Voice, Data, and Video Network.

LAS VEGAS -- Spirent(R) Communications (NYSE:SPM) (LSE:SPT) today announced that Spirent Advanced Test Programs (ATP) contributed an array of test equipment as well as professional services and support to the first enterprise triple play test, staged by the University of New Hampshire Interoperability Laboratory (UNH-IOL). Test results are being announced today and can be referenced at ftp://ftp.iol.unh.edu/pub/whitepapers.

Spirent Communications is a worldwide provider of performance analysis and service assurance systems for next-generation network technologies. The test employed Spirent Abacus 5000, Avalanche/Reflector, AX/4000 and SmartBits(TM), which together offer a complete solution for triple play network testing.

Enterprises have begun to deploy complex wired and wireless networks to support an unprecedented combination of triple play data, voice and video applications over a common infrastructure. As detailed in the white paper, the UNH-IOL initiative was the first organized multi-vendor test event that validated the interoperability, performance and scalability testing of such triple play networks. Conducted March 21-25, 2005, the tests incorporated hardware and software products from 13 suppliers.

"Spirent Communications' testing resources tackled every layer of this complex, multidimensional network," said Gerard Goubert, manager of the UNH-IOL wireless and VOX (Voice over Anything) consortia. "Technologies and professional services such as Spirent's will undoubtedly play a vital role in triple play testing overall."

Spirent's start-to-finish participation in the tests demonstrated its leadership in comprehensive, Layer 2 through Layer 7 triple play network testing and validation. The company's professional services engineers provided test requirements assessment, methodology development and network staging services. These contributions were deployed over several Spirent Communications' systems, with onsite support throughout the event.

"Spirent provided the most comprehensive Layer 2 through 7 testing tools and expertise to help drive the interoperability, performance and quality of these cutting-edge technologies," said Mark Fishburn, vice president, technical strategy, Spirent Communications. "UNH-IOL has provided the industry a great service by conducting tests of triple play networks at the vanguard of their emergence in enterprises everywhere."

In pre-deployment, UNH-IOL used the Spirent SmartBits Performance Analysis Test System to determine convergence, latency, packet loss, throughput, and other performance measurements of LAN switches and routers using Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP). UNH-IOL also used the Spirent AX/4000 Broadband Test System for STP and RSTP conformance testing to uncover any protocol implementation problems early in the development cycle. AX/4000 offers the broadest protocol coverage in the industry, including ATM, Frame Relay, optical and routing at speeds up to 10 Gbps.

Once the network was built, UNH-IOL tested with the Spirent Abacus IP Telephony test system to assess and validate both media and signaling functions and to determine and attain the highest voice quality results from the network. UNH-IOL also employed Spirent Avalanche/Reflector load testing to optimize the infrastructure for triple play. Avalanche/Reflector simulates the full range of network applications, including Real-Time Streaming Protocol (RTSP) and Microsoft Windows Media video streaming, under real-world traffic loads, user behavior emulation and network and device configurations.

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

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