Hier eine kurze Beschreibung der Funktionalität von 3CX :

3CX Phone System is a software-based IP PBX for Windows (1) which replaces traditional PBX hardware phones. It is based on the SIP standard and supports standard SIP software / hardware phones. It allows calls to be made via a VOIP service provider or via the regular PSTN. Easy to install and configure, it includes a web-based configuration interface, voice mail, auto attendant, call hunting and other features. Both commercial and a free edition are available.

(1) - Microsoft Windows ist eine eingetragene Marke der Firma Microsoft.