Microsoft has issued a release candidate of AppFabric, a services platform capable of automating the addition of key features in .Net applications.

AppFabric is designed to ease development problems in future Windows .Net applications. It will become generally available in June, and at some point will become a standard feature of Windows Server 2008.

AppFabric is slowly gaining power and potential use among Windows developers as Microsoft builds out its capabilities. Microsoft first aired a set of goals for AppFabric, whether applications are running on premises or in the Microsoft Azure cloud, at the Professional Developers Conference in L.A. last November.

Now as a release candidate, it's close to being a product capable of standing on its own two feet. By the time it's part of Windows Server at an unspecified date, many developers will already be familiar with its capabilities.

Another point in its favor is that AppFabric has been more thoroughly tied into Microsoft's integration server, BizTalk Server 2010, which is scheduled to be to become generally available in the third quarter. Thus Microsoft is pushing ahead with increasing integration capabilities between its technologies as it tries to command the high ground of future application development.

A new generation of applications will soon be built to run not only in the traditional data center but in cloud computing environments as well. Microsoft knows it will face a new round of competition with Java as it also achieves new levels of integration in the Spring Framework, now part of VMware, and Eclipse-based tools. "The role of application infrastructure has become a mission-critical function in all types of businesses today, which creates demand for high-performing, connected systems," said Abhay Parasnis, general manager of the Business Platform Division at Microsoft, in the May 20 announcement.

Burley Kawasaki, director of developer platform management, including BizTalk, said if a major shift in technology is underway toward cloud computing, then it's important for Microsoft to tie BizTalk and AppFabric more tightly together. "Every time there is a generational shift (such as mainframe to client/server), middleware plays a key role," he observed in an interview.