Web services are coming of age as pioneering early adopters move proof-of-concept implementations into more robust deployments, industry watchers have reported.

According to research from IDC, $2.3bn was spent worldwide on web services software in 2004, more than double the amount from the previous year.

The analyst firm expects spending to continue to increase "dramatically" over the next five years, reaching approximately $14.9bn by 2009.

"Web services are expected to become even more pervasive throughout the entire computing stack," said Sandra Rogers, programme director for SOA, web services and integration research at IDC.

"Web services have been and will continue to be adopted primarily by technology vendors that then proliferate the use and consumption of web services via integrated solutions, more so than enterprises addressing all the development and processing complexity directly."

The IDC study predicts that the web services market will be characterised by continued vendor and product consolidation during the next five years.

The study also expects the market to go through a period of flux with growing price pressures and shifting licensing models accompanied by major product version releases by key vendors.

According to the report, the web services development, deployment and information access marketplace is currently the largest primary web services software category.

The analyst expects that web services applications software will ultimately experience the highest growth through to 2009.

From a regional perspective, nearly two-thirds of the web services software market is currently concentrated in North America, primarily in the US, and the region will continue to host the majority of the market through to 2009.