Spirent Communications Launches Integrated Testing Initiative with New Avalanche Software Release.

Business Editors/High-Tech Writers

ROCKVILLE, Md.--(BUSINESS WIRE)--Oct. 20, 2003

Network Edition 6.0 Software Leverages Spirent's Avalanche and

SmartBits Product Lines to Enable Customers to Effectively Test Wide

Range of Layers 2-7 Technologies

Spirent Communications(TM) (NYSE:SPM)(LSE:SPT) today announced it has developed a new test solution that will allow customers to use two of the company's leading product lines to more effectively test a wide range of Layers 2-7 technologies. Spirent's Network Edition 6.0 software leverages Spirent's Avalanche(TM) and SmartBits product lines and signals a significant step in the company's focus to deliver innovative solutions for Layers 2-7 testing. With this new solution, network equipment manufacturers and service providers will be able to effectively test products within the Layers 2-7 stack and capture application metrics that better reflect the end-user experience.

Application-level metrics are the only true indication of infrastructure performance, and integrated testing and reporting allows more accurate assessment of networking products. The new capabilities in Network Edition 6.0 will enable users to more comprehensively test their products prior to shipment and to identify potential application performance issues earlier. Additionally, the new release provides two more important features for equipment manufacturers: the ability to test any proprietary protocol and the capability to support the higher performance TeraMetrics XD line cards with dual media capabilities.

"Application metrics are a critical piece of ensuring end-to-end interoperability for all devices, whether or not those devices have any native application-aware capability," said Elisabeth Rainge, program director network management at IDC. "The Layer 7 measurements anticipate the needs of enterprise customers in a way that could clearly improve the ROI of the network device for the enterprise IT department."

Network Edition 6.0 software includes the following new features:

-- AfterBurner(TM): offering an effective method for testing

extremely high-end firewalls, server load balancers (SLBs) and

large-scale infrastructures. Spirent's Avalanche AfterBurner

enables in excess of 300,000 TCP connections per second on a

single Gigabit link.

-- Application Capture and Replay: leveraging Avalanche's

proprietary high-performance TCP/IP stack, this feature

enables users to easily test proprietary application protocols

with realistic traffic at high rates without requiring them to

develop special testing software.

-- Streamliner(TM): specialized technology that enables testing

of Web protocols at 20 to 30 per cent higher performance,

while maintaining extreme realism with a fully compliant

TCP/IP implementation.

-- Dual Media support: tight integration with the TeraMetrics XD

cards which enables users to test gigabit wirespeed TCP

connections per second while supporting both copper and fiber

interfaces with one module.

Additionally, Network Edition 6.0 software provides improved automation capabilities and boasts an enhanced control and GUI architecture that allows it to integrate with other leading products in Spirent's portfolio, including those designed to test Layers 2-3 devices such as routers and switches. The combination of Avalanche and SmartBits with other Spirent products enables more productive, comprehensive and effective integrated testing of all network devices and infrastructure.

"As Foundry's ServerIron continues to set new records in industry performance and security, we place great demands on the test tools and equipment to drive the traffic and test our products," said Chandra Kopparapu, vice president and general manager of Foundry's Service Provider and Multi-Layer Switching Business Unit. "Spirent's new products and innovations enable us to continue our own product innovation and set new industry records."

Network Edition 6.0 software for the Avalanche/SmartBits product line will be available in 30 days.

About Spirent's Avalanche Product Line

Avalanche is designed for network equipment manufacturers, service providers and Web site managers that demand absolute realism and control under all conditions. Avalanche challenges any computing infrastructure's ability to stand up to the load and complexity of the real world. Avalanche can generate in excess of 30,000 HTTP requests per second, and supports HTTP/1.0, HTTP/1.1, HTTPS, RTSP/RTP (Apple QuickTime(R)), RealSystem(R) streaming, Microsoft(R) Windows Media(R) 8 and 9 Series, SMTP, POP3, DNS, Telnet and FTP. In addition, Avalanche can generate Distributed Denial of Service attack traffic inline with any mix of multi-protocol traffic. Through clustering, Avalanche can scale to the needs of even the world's largest infrastructures. Many leading corporations use Avalanche to ensure that their products and services excel in real-world conditions. Real-world conditions are accurately replicated by simulating error conditions, realistic user behavior, and maintaining over one million open connections from distinct IP addresses. Current customers include AT&T, BEA, Cable & Wireless, Cisco Systems, CNET, Deutsche Bank, eBay, Extreme Networks, F5 Networks, Forbes.com, Foundry Networks, Intuit, MSNBC, Network Appliance, NetScreen, Nortel Networks, NTT DATA, SBC Communications, and WatchGuard. http://www.spirentcom.com/avalanche

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 enable customers to develop and deploy network equipment and services more economically and efficiently by emulating real-world conditions in the lab and assuring end-to-end performance of large-scale networks. 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). 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.

This press release may contain forward-looking statements that are based on current expectations or beliefs, as well as assumptions about future events. By their nature, forward-looking statements are inherently predictive, speculative and involve risk and uncertainty because they relate to events and depend on circumstances that will occur in the future. You should not place undue reliance on these forward-looking statements, which are not a guarantee of future performance and are subject to factors that could cause Spirent's actual results to differ materially from those expressed or implied by these statements. These risks include the risks described from time to time in Spirent's SEC periodic reports and filings. We undertake no obligation to update our forward-looking statements, whether as a result of new information, future events or otherwise.