Microsoft is getting ready to make a big splash into the VoIP pool with its OCS 2007, expected to ship this summer.

When OCS's software-based VoIP engine is coupled with Microsoft Office Communicator 2007 client software, users have access to IP telephony, instant messaging and presence awareness. Furthermore, when Microsoft Exchange 2007's unified messaging services (see story detailing these capabilities) are added to the mix, voice mail and autoattendant features also are on the table.

The pieces add up to a solid foundation for presenting voice at the desktop. Microsoft is quick to point out that it is not proposing to replace the traditional IP PBX with this combination; rather, it touts its standards-based Session Initiation Protocol (SIP) ties for trunking and communications with traditional PBX systems. To that end, we note that some core IP PBX features, such as call park and whisper page, are not available in this version of OCS, nor are many of the call-routing and -handling features of traditional IP PBX back-end systems.

That said, taking into account the IP-telephony focus the combination -- OCS 2007, Office Communicator 2007 and Exchange 2007 -- offers Microsoft shops, our testing of the public beta code evaluates how far Microsoft does go in terms of providing enterprise-ready IP PBX capabilities.