The worldwide unified communications (UC) market surged past the $500m (£303m) mark last year after growing 16 per cent.

The UC and IP Contact Centre Market Share and Forecasts report from Infonetics Research finds global revenues from unified messaging kit and communicator software reached $523.4m in 2008.

Growth slowed in the communicator client segment as shipments spiked 47 per cent to 1.4 million. In 2007 volumes almost trebled as the alliance of vendors Nortel and Microsoft fuelled demand.

In the high growth communicator market Cisco enjoyed a successful year as it leapt from the number five position to become the market's top vendor by revenue. Siemens and Avaya are nigh-on inseparable in second and third spots respectively.

Worldwide revenues in the IP contact centre arena grew 54 per cent last year to $956m. Infonetics claims this growth was driven by strong demand in the Asia Pacific region and the continued transition from TDM to IP telephony. Avaya led the market by revenue with Alcatel-Lucent and Cisco filling out the podium positions.

Matthias Machowinski, directing analyst for enterprise voice and data at Infonetics, claimed he expected the overall UC market to double in size this year.

"Unified communication enables workers to communicate more effectively with mobile and geographically dispersed colleagues and to integrate multi-modal communication services to help increase productivity," he said.

"These drivers, combined with aggressive bundling by PBX vendors to increase the competitiveness of their offerings – and to fend off the threat to the PBX business from Microsoft – will push the UC market to relatively good growth in 2009."