Spirent Communications Delivers Two New Solutions for Integrated Voice, Fax and Data Modem Testing.

Business Editors/High-Tech Writers

ROCKVILLE, Md.--(BUSINESS WIRE)--Dec. 10, 2002

New Voice Resource Generator Cards Emulate Client/Server

Modem Traffic to Measure Functional and Performance

Capabilities of Converged Networks

Spirent Communications(TM), a wholly owned business group of Spirent plc (NYSE:SPM) (LSE:SPT), today announced two new test solutions that combine voice, fax and data modem test capabilities into single card solutions. Subsystems of Spirent's Abacus1 and 2 solutions, the new Voice Resource Generators (VRG1 and VRG2) provide a full range of capacity testing and emulate high-density V.90 or newly adopted V.92 modem technology for both client and server modem traffic.

Designed to meet the variety of user testing requirements, Spirent's VRG1 test card provides capacity testing for up to 72 data modems or fax machines for circuit generators (CG), while the VRG2 test card supports up to 504 data modems or fax machines. VRG2 boasts notably high-capacity test capabilities as well as a very low price point per channel.

The new high-capacity cards eliminate the need for fax and modem manufacturers, and service providers to purchase multiple test card solutions. Utilizing one of Spirent's single-card VRG solutions, network equipment manufacturers are able to transmit a converged mix of fax, data and voice traffic at the same time, in order to validate the performance of their devices and expedite time to market. Additionally, Internet service providers can leverage the new Spirent solutions to verify service capacity capabilities and optimize bandwidth to assure enhanced subscriber services.

"V.90 and V.92 modem technology continue to be the most popular methods for Internet access, therefore the converged network architecture needs to consistently and reliably deliver business-critical voice, data and fax services," said Bahaa Moukadam, vice president of product marketing, Spirent Communications - Performance Analysis Broadband. "Spirent's VRG cards aim to save customers time and money by enabling the necessary network and device reliability testing in single-card solutions."

Specific features of Spirent's new VRG test cards include transmitting user-defined testing patterns, viewing the received test page, tracing information that reveals the details of each phase of a fax transmission and reporting connection speeds, throughput, and line-error rate for each channel. For data modem testing, both VRGs support Bell 103, Bell 212, V.21, V.22, V.22bis, V.32, V.32bis, V.34, V.90 and V.92, reporting connection speed, throughput, ping round-trip delay and bit-error rate testing for each channel. Users can send/receive ping and test FTP over a modem link by downloading or uploading files to an FTP server. Additionally, VRG1 can be used to test voice quality using PSQM or PESQ and VRG2 provides the CODECs emulation and PESQ voice quality testing for VoIP legacy and converged networks.

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. 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

Note to Editors: Spirent, Spirent Communications and the Spirent logo are trademarks of Spirent plc. All other trademarks or registered trademarks are held by their respective companies.

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