ROCKVILLE, MD-- Nov 19, 2002 -- Spirent Communications, a wholly owned business group of Spirent plc (NYSE:SPM) today announced its successful participation in Global Multi Service Switch Forum (MSF) Interoperability 2002 (GMI 2002), the industry's first live networked test and demonstration event for the MSF's Release 1 Architecture.

The test, which took place from November 4-15, was conducted in a real-time networked environment simultaneously between three different sites -- one each in North America, Europe, and Asia. Spirent's participation in GMI 2002 was spearheaded by its Advanced Test Program (ATP).

"MetaSwitch shares Spirent's commitment to supporting the MSF Release 1 Architecture -- and participation in the MSF GMI 2002 was a key step in demonstrating global interoperability," said Paul Brittain, Senior Product Manager at MetaSwitch. "Support from Spirent was crucial in setting up and running the test scenarios."

GMI 2002, comprised of four voice scenarios and one data scenario, aimed to successfully demonstrate MSF's Release 1 Architecture utilizing the MEGACO H.248, Bearer Independent Call Control (BICC), and Session Initiation Protocol (SIP) as the main control and signaling protocols.

Spirent was the only participating test vendor with the capability to provide an end-to-end test environment with MPLS transport emulation and voice call set-up and tear-down.

More specifically, Spirent provided its award-winning Adtech AX/4000 to demonstrate the use of MPLS and MPLS VPNs for secure transport of VoIP networks and traffic engineering.

Spirent's Abacus2 SIP, MGCP, and MEGACO VoIP capabilities also were featured. The Abacus2 was used to terminate and provide Voice Quality Analysis for SIP calls. Spirent's Abacus1 was used for analog and SS7 signaling to generate and terminate voice calls over analog and TDM T1 and E1.

Spirent's offering helped facilitate the MSF's validation of the Release 1 Architecture test scenarios, and each vendor's testing and validation of its own equipment's ability to interoperate with other equipment.

Spirent provided equipment and engineering support in all three labs:

- BTexact Technologies' Advanced Research and Technology Centre, Adastral Park, Martlesham, Ipswich, England

- NTT's Musashino Research and Development Center in Tokyo

- University of New Hampshire Interoperability Lab, Durham, NH

About GMI 2002

Global MSF Interoperability 2002 (GMI 2002) was the first-ever interoperability demonstration of a multi-service architecture designed by a broad mix of major carriers, network equipment manufacturers and test equipment vendors. The Multiservice Switching Forum's Release 1 Architecture was tested November 4-15 simultaneously at three test sites, across three continents -- one each in North America, Europe and Asia. The primary goal of GMI 2002 was to demonstrate MSF's Release 1 Architecture utilizing MEGACO H.248, Bearer Independent Call Control (BICC) and Session Initiation Protocol (SIP) as the main control and signaling protocols. For additional information on the event please visit http://www.msforum.org/.

About Spirent's Advanced Test Program (ATP)

Spirent's ATP, in existence since 2000, is the first of its kind in the communications sector offering programs and expertise specifically designed to support key organizations conducting the industry's most advanced test and measurement activities. The ATP team supports test labs at leading universities, publications, trade shows, consortia, and advanced research facilities, as well as the industry's most prestigious independent testing organizations. ATP is a worldwide initiative that coordinates critical testing and research support across all divisions of Spirent Communications.

About Spirent Communications

Spirent Communications is a worldwide provider of integrated performance analysis and service assurance systems for next-generation network technologies. Spirent's solutions accelerate the profitable development and deployment of network equipment and services by emulating real-world conditions in the lab and assuring end-to-end performance of large-scale networks. http://www.spirentcom.com/

Spirent Communications is a wholly owned business group of Spirent plc, an international network technology company. Spirent plc is listed on the London Stock Exchange (ticker: SPT). The company is also listed on the New York Stock Exchange (ticker: SPM; CUSIP number: 84856M209). http://www.spirent.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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Contact:
Contact: Cathi Lane
Company: Spirent Communications
Title: Director, Public Relations
Voice: 818-676-2364
Email: cathi.lane@spirentcom.com