As the application acceleration market continues to change, industry watchers say the technology's role in enterprise IT shops will continue to grow in importance - and revenue dollars will increase for vendors.

Market research firm Gartner recently estimated that the market for application acceleration products will reach $1.5 billion in 2005, a 33% increase over 2004. And the firm estimates that by 2009 the market is expected to reach about $2.3 billion in end-user sales.

Gartner classifies application acceleration products as appliances that "enable server/data center consolidation and deployment of browser-based application interfaces while lowering total cost of ownership." The firm puts the technologies into two buckets: application delivery controllers (ADC) and WAN optimization controllers (WOC), according to a press release.

According to Gartner research as of July 2005, Cisco was the market leader in the worldwide ADC market in the first quarter of 2005, however, the company lost market share since the fourth quarter of 2004 and was nearly eclipsed by F5 Networks. And Gartner says competition among the WOC vendors remained "intense" in the first quarter of 2005, as Network Appliance, Packeteer and Stratacache led the market.

Recent activity in the market - such as Citrix acquiring NetScaler, Juniper buying Peribit and Redline Networks and Cisco picking up WAN traffic accelerator FineGround Networks - all point to a bigger trend of vendors offering multiple WAN acceleration technologies on fewer appliances.

"The trend toward powerful platforms that deliver four or more functions will accelerate as customers strive to simplify their infrastructure, and as vendors move to grow revenue and increase account control," Joe Skorupa, research director for Gartner, said in a press release. "Cisco, Citrix and Juniper have entered into this important market, and consolidation will continue as strong platform vendors acquire promising software providers that have not reached critical mass. Other vendors will forge partnerships to acquire products to round out their portfolios."

Ann Bednarz is associate news editor at Network World.