Chrome Extension (WebRTC/SIP , DNS)

A chrome extension need to be created which can make and receive calls through SIP protocol, extension may use WEBRTC or if it can be built without WEBRTC that would be much better. Extension need to identify for the PORT given, that if port is available to be connected or not and in local network at which IP the given port is available so if IP changes extension can detect automatically. Extension will show user if there is any incoming call. And there may be some need of configuration to send some particular information on SIP like Dialler Name, Number etc.