W. CONSHOHOCKEN, Penna. – January 23, 2006 - Spirent plc (LSE: SPT; NYSE: SPM), a leading U.K.-headquartered communications technology company, today announced that it has entered into an agreement to acquire SwissQual Holding AG (“SwissQual”), a pioneering Swiss-based provider of innovative test and measurement systems and solutions for wireless telecommunications markets.

The consideration is CHF 62.5 million payable in cash at closing plus up to CHF 28.0 million payable during 2006 and 2007 based on achievement of certain revenue targets and technical milestones.

Fairmount Partners of West Conshohocken, PA served as financial advisor to SwissQual and structured and negotiated the transaction on behalf of SwissQual.

SwissQual was founded in 2000 and is headquartered in Zuchwil, Switzerland. SwissQual also has sales offices in Rome and Singapore. Currently, SwissQual has approximately 80 employees.

SwissQual provides innovative systems and solutions to telecommunications network operators and equipment providers for measuring, monitoring and optimizing the quality of voice, data, video and messaging services. SwissQual’s broad portfolio of products can be used for: benchmarking service quality on an operator’s and across competitors’ networks; delivering detailed information to enable operators to troubleshoot and improve wireless service performance; and evaluating the service performance of fixed and wireless network equipment.

In the year ended December 31, 2005, SwissQual reported sales of CHF 32.1 million with EBITA of CHF 5.5 million, up from CHF 23.3 million and CHF 4.8 million in 2004, respectively.

The acquisition of SwissQual is expected to increase Spirent’s wireless market position by bringing exposure to a new market area (Subscriber Experience Management, which measures the quality of the subscriber’s experience and service received from a user perspective rather than a network perspective) together with access to technology that enables Spirent’s entry into the video-intensive handset applications test market. In addition, SwissQual brings with it a high-quality European customer base of wireless network operators and a number of organic growth opportunities.

SwissQual will be incorporated within Spirent’s Performance Analysis Division and SwissQual’s experienced management team will continue to manage the business.

About Spirent

Spirent is a leading communications technology company focused on delivering innovative systems and services to meet the needs of customers worldwide. Spirent is a global provider of performance analysis and service assurance solutions that enable the development and deployment of next-generation networking technologies such as broadband services, Internet telephony, 3G wireless and web applications and security testing.