几种SIP开源协议栈分析
NIST SIP
Java SIP stack as reference implementation of JAIN API, so it's has good API and documentation. It also has reference implementation for servers and user agent.
GUI user agent and SIP stack with focus on security, and is portable across Win32, Windows Mobile, Linux, and Linux iPaq. Supports audio and video. [LGPL].
SIP stack written in Java, with layered API approach. Applications include servers and user agent with audio and video capabilities. [GPL]
SIP stack with media, written in C++ and depends on PWLIB. The website has reference implementation for SBC and also an ActiveX component for building SIP user agents.
Footprint is quite large (megs?), but it has media stack implementation (with video?) too. [MPL]
One of the earliest open source SIP stack, so it enjoys good number of adopters.
Footprint is quite small (several hundreds KBs), and supported ports include Windows, Linux/*nix, VxWorks, MacOS X, and many embedded targets. Media stack is available via commercial license only. [GPL or commercial].
PhoneAPI from OpenWengo project, written in C. It says to provide easy to use high level API for developing SIP audio and video user agents.
Ports include Linux, Windows, and MacOS X. Media stack included. (GPL)
The SIP (and media) stack features in this website.
PJSIP SIP stack is written in C and is mainly targetted for small footprint, feature rich user agents, although it has attracted some server side developments too.
Footprint is very small (<200KB), performance is very good (thousands of calls per second), and it is very very portable (Windows, Windows Mobile (WinCE, PDA, SmartPhone), Linux, *nix, MacOS X, *BSD (FreeBSD), RTEMS, Symbian OS, etc.), which makes it good candidate for embedded developments. Complete media framework is available with PJMEDIA. [GPL or other]
C++ stack from SIPFoundry non-profit SIP community project. The community is backed by many commercial companies and it hosts health number of active developers. (Vocal)
A SIP library written in C for building SIP clients. Supports many SIP call, presence, instant messaging features, as well as TCP, IPv6, TLS, and STUN support.