SPIRENT FEDERAL Participates in Military's Largest Communications Exercise; Recognized for Support of JITC in Combined Endeavor 2005.

LAGER AULENBACH, Germany -- Spirent(R) Federal Systems today announced it was recognized by military leaders for the company's outstanding support during Combined Endeavor, the largest communications and information system (CIS) military exercise in the world. During the exercise, Spirent Federal Systems supported the Joint Interoperability Test Command (JITC) with a team of System Engineers and the latest test instrumentation.

Combined Endeavor 2005, a Partnership for Peace (PfP) exercise sponsored by U.S. European Command, brings together NATO and Partnership for Peace nations to plan and execute interoperability testing of command, control, communications and computer equipment systems from the participating nations in support of future combined humanitarian, peacekeeping and disaster relief operations.

"The JITC's role in Combined Endeavor is to ensure true interoperability. We manage the testing process and then document the results of the testing," said Army Lt.Col. Jerry Schlabach, Exercise Combined Endeavor's test director. "Spirent Federal's complete and thorough testing and onsite support is essential in helping us determine the interoperability between nations."

The Joint Interoperability Test Command (JITC), based out of Fort Huachuca, Ariz., is a field command of the Defense Information Systems Agency (DISA) and supports all the military services in their efforts to manage information both on and off the battlefield with the continual goal of achieving command, control, communication, computers and intelligence (C4I) interoperability.

43 nations, crossing four continents, are participating at the exercise this year and will conduct more than 1,400 different interoperability tests, with the main elements being satellite communications, video teleconferencing, voice over the Internet and single-channel radio networking. Spirent Federal is testing the ATM core network for capacity and latency and testing the interconnected router IP networks between participating nations. As part of the JITC team, Spirent Federal is using Spirent's Abacus 5000 to conduct Voice over IP and video testing and using Spirent's SmartBits(TM) Performance Analysis Test System with its Avalanche Web and Security Test System to simulate multiple users of the data network into command centers.

"We are honored to have been selected to partner with JITC for this important exercise," stated Jim Jordan, director, broadband for Spirent Federal. Spirent Federal provided the latest in test instrumentation and a team of System Engineers to provide technical assistance to various nations during the exercise.

"Ultimately, we want to make sure that when a crisis occurs, such as a natural disaster or a peacekeeping mission, the militaries of a multi-national force can immediately work together and communicate effectively," added LTC Joseph Angyal, the Combined Endeavor exercise director.

As a result of conducting these exercises, nations have been operationally successful in real-world operations including recent Tsunami Relief efforts and Operation Iraqi Freedom. Because of the many successes, similar Combined Endeavor exercises are being planned or considered for Africa and the Pacific region.

About Combined Endeavor

Combined Endeavor began in 1995 as a simple effort to bring NATO and former Warsaw-pact countries together under the auspices of NATO's Partnership for Peace, and has since taken place annually. Since 1995, nations have been involved in military operations in Bosnia, Kosovo, Afghanistan and Iraq as well as the recent support of humanitarian operations in the area affected by the Tsunami. During the past 11 years, Combined Endeavor has grown to 43 participating nations and has responded to the ever-changing CIS requirements of its militaries by setting and revising standards to enable communications interoperability.

About Spirent Federal Systems

Spirent Federal Systems Inc. (www.spirentfederal.com) was formed in July, 2001 by Spirent Communications as a proxy company. Spirent Federal markets and sells Spirent Communications products to U.S. government agencies. It also provides value-added features and ongoing customer support. Spirent Federal Systems is headquartered in Yorba Linda, Calif., with support and sales offices in Texas, Virginia and Maryland. www.spirentfederal.com

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.

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