What is "pbxnsip"

Pbxnsip is a software implementation of a telephone private branch exchange (PBX) produced by a company of the same name. Like any PBX, it allows attached telephones to make calls to one another, and to connect to other telephone services including the public switched telephone network (PSTN) and Voice over Internet Protocol (VoIP) services. Its name is a combination of the acronyms PBX and SIP ( Session Initiation Protocol).

Pbxnsip is released under a proprietary license with trial versions available on the pbxnsip website. Pbxnsip was acquired on October 4, 2010 by IP Phone maker Snom. Licensing has reportedly not changed.

Originally designed for Linux, pbxnsip now also runs on a variety of different operating systems including Microsoft Windows, Mac OS X and FreeBSD. There are also embedded versions available.