著名的sip协议实现。可以在上面进行二次开发，例如语音，voip，传真等。-Famous sip protocol implementation. Can be carried out in the above secondary development, such as voice, voip, fax, etc..

pjsip协议栈，开源的sip协议栈，很小巧，很有用的协议栈-pjproject-1.6：the Open Source, comprehensive, high performance, small footprint multimedia communication libraries written in C language for building embedded/non-embedded VoIP applications.

pjsip源代码,编译后可以实现短信息和音频通话，传输质量很好 速度很快-this is an open source SIP stack,it can be transmit message and audio communication

Sip 协议栈，基于WINDOW下，名字为：Spjproject-1.5.5.tar-Sip protocol stack, based on WINDOW, the name is: Spjproject-1.5.5.tar