Spirent(R) Communications Leads IMS Testing Efforts at the MSF GMI 2006 Interoperability Event.

Spirent Enabled 200 Next-Generation Elements at Five Global Sites to Navigate Testing Maze for Global IMS Validation

SUNNYVALE, Calif. -- Spirent Communications (NYSE: SPM) (LSE: SPT), a global provider of performance analysis and service management solutions, today summarized its significant contribution to the 2006 MultiService Forum (MSF) Global MSF Interoperability (GMI) event. Spirent Communications was the only test vendor able to provide test expertise at all five global event locations, and to contribute equipment that covered all test scenarios.

The GMI 2006 event demonstrated multi-vendor interoperability of Fixed Mobile Convergence (FMC) services using the IMS framework. Spirent test experts worked with IMS implementation teams across the world at BT, KT, NTT, Verizon and Vodafone lab sites. As IMS interoperability has not been standardized within the industry to date, Spirent saw many difficulties associated with deploying proprietary implementations between multiple service providers. Specifically many differences were observed in the operation of User Element devices and with differing interpretations of the core IMS protocols.

"This year's MSF GMI served to show the industry just how powerful IMS services will be. Alongside this vast potential is a tremendous amount of complexity," stated Naseem Khan, principal member of technical staff in Verizon's Technology organization. "Spirent's participation helped us unravel a large amount of the difficulties surrounding the differences between the implementation of proprietary call flows. Spirent's expert input around IMS testing methodologies highlights the need for standardized test plans to be adopted by the IMS industry."

"Spirent participation in GMI was crucial to the event's success. We allowed participants to navigate the myriad of possible test cases and scenarios within a controlled, repeatable environment," said Andy Huckridge, director of IMS Solutions at Spirent Communications. Huckridge also chairs the Interoperability Working Group within the MSF. "The unforeseen variables that were encountered during the GMI underscore the need for standardized test plans and specifications. These, in conjunction with an industry-wide interoperability and certification program, would go far to ensure the timely deployment of valuable IMS services."

During the GMI 2006 event, which ran from Oct. 16th - 27th, Spirent Communications provided experts, test equipment and advanced IMS test methodologies to facilitate the stringent testing requirements of MSF Release 3 implementation at all five carrier sites. This involved 200 next-generation network (NGN) elements tested against carrier defined test scenarios. Spirent's support included test coverage for all portions of the IMS network:

* IMS Access Network - Spirent provided real-world traffic models to evaluate wireless core packet data network elements associated with FMC applications.

* IMS Core Network - Spirent simulated UE (User Element) traffic and emulated the core network elements

* PSTN Network - Spirent emulated end to end traffic and all PSTN network elements.

* Service prototyping - Spirent simulated many Next Generation Network services

Investment in groundbreaking events like GMI 2006 and relationships with service providers and vendors pursuing their IMS roadmaps have given Spirent unparalleled depth and breadth of testing and implementation expertise. These groups are partnering with Spirent to accelerate the timeframe from design to revenue by assuring IMS implementations are ready for deployment before they are actually deployed. More information about the MSF GMI event can be found at www.msforum.org.

About Spirent Communications

Spirent Communications, www.spirent.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 Communications' solutions are used by more than 1,700 customers in 30 countries, including the world's largest equipment manufacturers, service providers, enterprises and governments. Based in Sunnyvale, CA, Spirent Communications has 1,800 employees worldwide. Spirent Communications plc Ordinary shares are traded on the London Stock Exchange (ticker: SPT) and on the New York Stock Exchange (ticker: SPM; CUSIP number: 84856M209) in the form of American Depositary Shares ("ADS"), represented by American Depositary Receipts, with one ADS representing four Ordinary shares. Spirent Communications' sales to the United States government are made through Spirent Federal Systems Inc. www.spirentfederal.com

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

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