Spirent Communications Tests Triple Play Services End-to-End and Through Service Delivery.

CHICAGO -- Spirent's Comprehensive Test Portfolio and Global Services Assures Performance of VoIP, IPTV, Multimedia Streaming, Data and Other Converged Services

Spirent Communications (NYSE:SPM) (LSE:SPT) today unveiled it's proven approach to assuring QoS for bundled services -- 20 critical test scenarios that enable service providers to successfully implement quality of service (QoS) to ensure customer loyalty. Spirent's scenario approach to triple play testing evolved from its hands-on professional services work with more than a dozen service providers worldwide -- including all of the big four in North America.

Telecom service providers are racing to deploy bundled, triple play services. Data and voice are table stakes but the deciding factor will be video delivered on the same network, be it IPTV, video conferencing, video telephony or video-on-demand.

"Converged services are the future of the communications industry," said Matt Davis, director -- Broadband Access Technologies, Yankee Group. "Yet readying networks to deliver and grow with these services is a multi-dimensional undertaking -- there are many potential pain points. Extensive testing is essential to assuring QoS -- especially when bringing video into the mix."

Spirent's new solutions leverage its key differentiators: breadth of technologies, methodologies, and products together with its global services. The rich set of both point and system wide solutions can be used individually or combined to gain insight into the interaction between infrastructure, services and triple play applications.

"Only Spirent tests QoS for each network element, end-to-end across the network and then continues monitoring QoS after deployment," said Anders Gustafsson, CEO of Spirent plc, parent company of Spirent Communications. "Our integrated test and service management solutions enable service providers, network equipment manufacturers and enterprises to thoroughly validate the readiness of converged networks to deliver high quality and reliable IP video services."

Spirent's new testing scenarios address the unique challenges converged networks services present, including:

--Voice, video and data applications load testing;

--Large scale emulation of VoIP terminal, set-top, cable modem and other devices;

--Voice and video quality measurements;

--Real-Time Protocol (RTP) with IPTV tests;

--Testing of content such as unicast and multicast video and channel change times;

--Dynamic IP network impairment tests

--Testing of all elements of Carrier Ethernet as triple play infrastructure

Spirent's triple play solutions incorporate a broad suite of test systems for lab and pre-deployment testing (Avalanche(TM), Abacus 5000(TM), AX/4000(TM), Spirent Converged Network Impairment Emulator, mAXSLAM(TM), TestCenter), as well as post deployment and service management (SmartSight(TM) BRTU, SmartSight QoS Scope and CopperMax(TM)).

There are 20 new Spirent Triple Play test scenarios that cover the breadth of testing required to deliver required QoS to the customer. Testing each network element, end-to end and managing the quality of services in the deployed network are all critical in today's battle for reliable delivery of bundled triple play 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. 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, 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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