Real-time Communications (RTC) Client API

MSDN: Real-time Communications (RTC) Client API

Supinfo Paris: Use of the RTC API under Visual Studio .NET

VC知识库: 用微软的实时通信API集成丰富的客户端通信 翻译：孟谨
Here is some sample codes on XP, the original source on MSDN is not no longer existed.