This type of integration with a PBX relies on the installation of a voice board in the Unity server and it is being somewhat superseded by the use of the Intel PBX IP Media Gateway (PIMG).
The method of integration of the voice board can be realized via:
- Serial interface : In this case, you can configure parameters including phone system manufacturer settings, MWI On/Off codes, serial integration packet settings, COM port settings, voice messaging port configuration settings and so on
- Analog interface : In this case , you can configure parameters including phone system manufacturer settings, MWI On/Off codes, voice messaging port configuration settings and so on
With Serial integration, there are several cabling configurations. The followings are two common one:
- An RS-232 cable directly connects the Unity server and the phone system. So link between the messages lines are direct between the Unity and the phone system.
- An RS-232 cable connects the Unity Server and a PBXLink box and digital lines connect the PBXLink box and the phone system.
When using an PBXLink box, the phone system sends information including the called party extension, calling party extension (if available) and the reason for forwarding to the PBXLink.This communication between the PBXLink and the Unity is performed via Simplified Message Desk Interface (SMDI) packets. Unity activates/deactivates MWIs using analog messaging ports (not the serial which is used).
When using an analog integration, voice messaging lines (analog lines) directly connect the Unity and the phone system and the communication is done this time via DTMF sequences.