Paging: when you dial one number, the specific extension will answer it automatically, and the caller can speak anything, but the callee just can hear.
Intercom: when you dial one number, the specific extension will answer it automatically, and the caller and callee can make a normal call.
If you are using elastix as sip server, and you hope to use paging and intercom, you must make sure the IP phone support the function firstly, and then the related setting of elastix is as follows:
Paging extension: 100 means when we dial this number, the function will be actived.
Group Description: Grace team is the name of the function.
Device list: we can choose the related extension, it means when we dial 100, the related extension will answer it automatically.
if we want to choose multiple extensions, we can press ctrl key.
Force if busy:if we enable it, when we dial the paging number, if the extension is in one call, the phone will hold the current call and then go to paging.
duplex:if you enable it, it will be intercom. if you disable it, it will be paging.