P2P SDKs

Microsoft P2P SDK uses IP v6 technology. Its 3 degrees application requires you to pre-install many other software, such as Microsoft Messenger, service packs, Passport, TCP/IP packages, etc. And, it forces you to use Windows XP. Microsoft P2P SDK is a classical example of the corporate integration approach. [excerpt from this word doc]
Windows Real-Time Communication Client SDK
SIPShare
All Peers