Moonv6 Advances with November Test Set; Spirent Maintains Key Role in U.S. Department of Defense IPv6 Assessment.

ROCKVILLE, Md. -- National Test Network and Leading Testing Company Make Progress on New Internet 

Spirent Communications(TM) (NYSE:SPM)(LSE:SPT) announced that the Department of Defense's (DoD's) Joint Interoperability Test Command (JITC) used Spirent's test methodology, equipment and engineers during the November Test Set of the Moonv6 Test Project to plan and prepare for the future of DoD IPv6 implementation milestones. Following on Moonv6 Phase I and Moonv6 Phase II, the November Test Set was the third event of testing across Moonv6, the world's largest multi-vendor IPv6 network. The objective of this test, which wrapped up on Friday, Nov. 12, was to move the IPv6 technology forward through more advanced deployment style and functionality testing.

"Spirent's testing equipment and support have been essential to the IPv6 testing at JITC," said Captain Daniel R. Millane, USMC, JITC test director for Moonv6. "Spirent's ability to simulate real traffic and stress conditions over the Moonv6 network allowed us to see how the IPv6 network performs under various loads. In addition, Spirent's ability to report on throughput, latency and packet loss helped us understand where we need to go for future testing of IPv6."

In this round of testing, the November Test Set determined to what extent current DoD applications and vendor IP implementations, including hardware and software, interoperate when using select IPv6 features in a native IPv6 and dual IPv4/IPv6 environments. The network encompassed sites at multiple locations nationwide and expanded to include more sites than during Moonv6 Phase II. The testing, which was conducted from Nov. 1 to Nov. 12 by the JITC, and Oct. 30. to Nov. 12 by UNH-IOL covered: Mobility, Information Assurance/Security (Firewalls, IP Sec, PKI), Wireless 802.11g, Transition Mechanisms, IP Routers/Switches (QoS/CoS) and Vendor/DoD applications. The November Test Set involved verification of areas that have been previously tested, including security and dual stack transition mechanisms, and new areas of testing, including vulnerability and DoD developed applications, such as the JITC's Project Accounting System.

"At Spirent, we're looking forward to expanded acceptance of IPv6 from within the DoD to commercial and Enterprise markets for all the benefits that IPv6 offers, from the restoration of the Internet end-to-end model to an almost unlimited address space, stateless auto configuration, inherent mobile IPv6 optimizations and mandatory IPsec in implementations," said Jim Jordan, director of broadband for Spirent Federal. "Through participation in the November Test Set, we have gained more exposure and expertise in performing the actual testing; and by helping the DoD, we are inspiring our own engineers to develop products quicker. It's a great fit."

About Moonv6

The Moonv6 project is a collaborative effort between the NAv6TF (North American IPv6 Task Force), the UNH-IOL, government agencies and Internet2. Taking place across the U.S. at multiple locations, the Moonv6 project represents the most aggressive collaborative IPv6 interoperability and application demonstration event in the North American market to date. For more information, visit the organization's Web site at http://www.moonv6.org.

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 2003 revenue of $394 million and has 1,800 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 or registered trademarks of Spirent plc. All other trademarks or registered trademarks mentioned herein are held by their respective companies. All rights reserved.

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