Monet Mobile Networks Standardizes On Spirent Communications Wireless Service Assurance Solution.

Business Editors/Hi-Tech Writers

ROCKVILLE, Md.--(BUSINESS WIRE)--March 4, 2002

Spirent Communications(TM), a wholly owned business group of Spirent plc (NYSE:SPM and LSE:SPT.), announced that Monet Mobile Networks, a Seattle-based provider of wireless Internet services, has agreed to deploy Spirent's unified wireless service assurance platform across its growing service area in the Midwestern United States.

Monet will use the Spirent platform to enhance visibility into its network landline infrastructure, the key transport component behind wireless service.

"Since we are pioneering CDMA 2000 1x, a new technology, insuring quality of service and customer satisfaction is key to its adoption," said Chris Craven, Monet's vice-president of field operations. "Spirent's integrated platform offers us a faster and easier way to test network circuits and to detect and isolate problems associated with them. By using a remote tool, we can resolve wire line issues real-time, thereby maintaining our high standard of service reliability."

Under the agreement, Monet will deploy Spirent's REACT(TM) remote test management OSS (operations support system), Mini enhanced Digital Test Access Unit (Mini eDTAU) and Broadband Remote Test Unit (BRTU), as well as the related central office engineering and installation required for rapid system deployment.

The Mini eDTAU provides direct test access to Monet's leased-line circuits, while the BRTU can provide modular test interfaces for diagnosing those circuits. Spirent's remote test OSS gives Monet a graphical interface for accessing circuits and associated network elements as well as automated test routines that return maintenance results, avoiding the traditional requirement for field dispatches.

The rapid deployment capabilities of the Spirent remote test OSS will also enable Monet to begin immediately testing circuits for acceptance, provisioning and maintenance.

"In offering untethered data services, Monet has a substantial opportunity to capitalize on the increasing prominence of wireless transport and the market's demand for affordable Internet access," said Jim Schleckser, president of Spirent Communications' Hekimian Division, which develops Spirent's unified wireless service assurance platform. "Spirent's unified service assurance platform will play an important part in Monet's service management strategy for delivering the highest-quality data service available in the air and on land."

About Spirent Communications

Spirent Communications (www.spirentcom.com) unites the best in performance analysis technology with network operations expertise. The company's award-winning products and solutions enable customers to accelerate the development, deployment and assurance of next-generation network equipment and services worldwide.

Spirent Communications designs and manufactures Adtech, DLS, Edgcumbe, GSS, Hekimian, SmartBits, TAS and Zarak products.

More than 2,500 of the world's leading network and terminal equipment manufacturers, network service providers, corporate enterprises and test laboratories rely on Spirent's first-to-market products to verify and measure the performance and services of networks and communications devices.

For more information on Spirent Communications or its products, visit the web site at www.spirentcom.com or call +1 800.927.2660.

Spirent plc is the parent of Spirent Communications. Spirent plc is quoted on the London Stock Exchange, ticker SPT. The company operates a Level 1 American Depository Receipt program (ticker: SPNUY; CUSIP number: 84856M100).

For information, contact Brian Heston, The Bank of New York, American Depository Receipts, 101 Barclay St, 22 West, New York, N.Y. 10286, phone [phone], fax [phone], email: [e-mail], www.adrbny.com. Further information about Spirent plc can be found at www.spirent.com.

About Monet Mobile Networks, Inc.

Headquartered in Seattle, Monet Mobile Networks Inc. (formerly Burst Wireless Inc.), was founded by telecommunications industry veterans in mid-1999. Monet is a wireless Internet service provider, offering users fast, mobile access to the complete Internet, email, corporate intranet applications, data and customer support.

The company's investors include Mayfield Fund, Soros Private Equity, Qualcomm, Intel Capital and Hook Partners. For more information, please visit www.monetmobile.com.

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