London-based Spirent plc said today it has acquired QuadTex Systems, a Dallas-based vendor of IP multimedia subsystem and voice-over-IP testing solutions. The deal will be carried out for $7.5 million, payable in cash on completion with up to a further $1.5 million payable depending on certain technical milestones and the retention of key employees, according to Spirent.

The acquisition is already Spirent's second of the year, the first being the $70.5 million acquisition of test gear manufacturer SwissQual just three weeks ago. Spirent said in a statement that QuadTex will be a good fit with its existing business, and will enhance its test capabilities in the areas of triple play, VoIP and IMS testing. IMS, which is being driven by fixed/mobile convergence, requires comprehensive and flexible protocol testing tools.

Spirent identified IMS and related fixed/mobile convergence as key areas of focus in a company presentation last December, during which Spirent also announced the proposed sale of its HellermannTyton network products unit.

QuadTex was founded in 2002, and employs just 14 people. In addition to its Dallas headquarters, it also has a development office in China. Shipment of its products began in the second half of 2004 and sales in 2005 totalled $2.0 million with rapid growth expected in 2006, according to the Spirent statement. Customers include Cisco, Ericsson, NTT and AT&T, with most revenues coming from deals in the U.S. market. The founders are expected to continue to manage the business which will be incorporated within Spirent’s Performance Analysis division.