For the second time in three months, Microsoft has acquired a Voice-over-IP (VoIP) startup—in this case, Swiss company Media-streams.com AG. The 23-person company was developing a software product called "e-phone"—client-side add-ins for Outlook and Lotus Notes and supporting server software that integrate VoIP phone capabilities into the e-mail clients so that PC users can take or receive voice calls directly from within Outlook or Notes.

Microsoft said that it plans to integrate Media-stream's people, technology, and intellectual property into the Real-Time Collaboration (RTC) Group, which oversees Live Communications Server, Live Meeting, and the Office Communicator 2006 client (its current business VoIP client). Microsoft also said that the Media-streams technology would appear in future Office products, although it gave no details on future product plans.

The acquisition appears to be mostly for Media-stream's back-end server software rather than the clients. Microsoft says that the acquired technology will accelerate the evolution of its RTC products by adding support for third-party VoIP phones that use the Session Initiation Protocol (SIP); for protocols used by gateways to PBX equipment; and for workgroup call-routing functionality (e.g., for directing calls to a pool of available help desk personnel). Microsoft did not say whether it would continue to support the Lotus Notes version of e-phone.

This acquisition follows closely on the heels on Microsoft's acquisition of Teleo, another small VoIP technology startup. However, the technologies are not directly related and Teleo will become part of the company's consumer-oriented MSN group, with its technology going into MSN's Messenger service.

The Teleo acquisition is described in "Voice over IP Startup Acquired" on page 28 of the Oct. 2005 Update.

Microsoft's recent efforts in business-oriented VoIP and telephony are described in "Taking Another Stab at Telephony" on page 9 of the Oct. 2005 Update.