Service-oriented architecture, or SOA, links business applications to provide services. By creating an architecture where applications communicate with each other, using protocols including Extensible Markup Language (XML), the aim is to enhance business processes. SOA requires open standards to link applications. These can be produced by third-party vendors or in-house.

IBM said on Monday that Microsoft's approach to SOA was stymied by its emphasis on linking Microsoft-compatible processes.

"We're doing all platforms, all applications," IBM Software Group executive Steven Mills told ZDNet UK. "We're integrating everything. Microsoft is trying to provide connectivity capabilities for those that are running on Windows platforms. That's a profound difference."