AsteriskWin32 (ver 0.66b) Abandoned Freeware AsteriskWin32 is a PBX system that can function as a SIP server (no addtional hardware is required). It is a Windows port of the Unix Asterisk software. Asterisk supports a number of hardware devices for interconnection with digital and analog telephony equipment. Asterisk provides Voicemail services with Directory, Call Conferencing, Interactive Voice Response, and Call Queuing. It has support for three-way calling, caller ID services, ADSI , IAX , SIP , H.323 (as both client and gateway), MGCP (call manager only) and SCCP/Skinny.