Sun Microsystems Inc. (JAVA) is set to unveil its new cloud computing product Wednesday, the latest entry into what is quickly becoming a crowded segment of the technology market.

The announcement of the Open Cloud Platform, which will offer storage and open-source computing applications, is Sun's attempt to grab a piece of the growing market for cloud computing, in which customers can access the computing power of off-site servers rather than build their own data centers.

The Sun cloud is based on open-source software, a major focus of Sun Chief Executive Jonathan Schwartz. Sun's open source business has been a bright spot amid sagging sales of its high-end servers. The company is betting that the popularity of its software among developers will translate to customers choosing its cloud over others already being rolled out by competitors.

Sun plans to offer two cloud services, available this summer: a storage service and a computing service.

The computing platform, Sun said, is focused on providing applications through a "virtual data center," which will allow customers to build a complete data center running any operating system within the cloud, including OpenSolaris, Linux or Microsoft's Windows.

Sun said that its products are primarily targeted at Web developers looking to quickly grow their businesses without making large infrastructure investments.

Over the past year, cloud computing has grown from a niche product to what many believe is the future for how companies will run their information technology infrastructure.

But the market is becoming crowded as companies from different sectors of the tech market converge on cloud computing as they scramble to find new sources of revenue.

Last year, Microsoft Corp. (MSFT) joined cloud pioneers Amazon.com Inc. (AMZN), Salesforce.com Inc. (CRM) and Google Inc. (GOOG) in the market, unveiling Windows Azure, a platform that allows developers to write Microsoft-compatible software that is stored and accessed on its servers. The tech giants are building data centers to deliver access to software services over the Web and flexible access to computer and storage resources.

Hopes are high for the adoption by businesses of the services, but many companies remain concerned about the security of their data and mission-critical applications running on servers that they don't physically control.

"The enterprise [segment], to my great surprise, is not at the inflection point yet, but they are very, very interested," said Lew Tucker, Sun's chief technology officer for the cloud business. "They are comfortable outsourcing their IT to companies, I think they will be comfortable outsourcing their cloud as well."

Tucker said the company plans to offer several cloud products targeting various market segments, from smaller tech start-ups to larger businesses.

And with many businesses wary of moving away from their own data centers into a larger, public cloud, Tucker said Sun's strategy is to create different products that allow customers varying levels of control.

For instance, some customers may choose to run all of their software on a Sun cloud that is accessed over the Web. However, Sun also plans to provide customers with services to help them create private clouds that can run on their own machines.

"There will be many clouds of many types of different sizes and capabilities," Tucker said.

-By Jerry A. DiColo, Dow Jones Newswires; 201-938-5670; jerry.dicolo@dowjones.com