We use legacy TDM based PBX system. What do we need to interface with a USN?
You will need to equip the PBX with additional T1/E1 CAS or ISDN cards to connect one or more T1/E1s between the PBX and the USN.
How should the trunking be set up between the PBX and the USN?
You will need a bi-directional Tie trunk between the PBX and the USN.
Inbound to USN: Set up a hunt group with number of channels equal to number of ports on the USN. For example, for a 48 port system set up a hunt group with 48 channels.
Outbound from USN: Calls originating from USN will be received by the PBX which in turn will route them to either internal extensions or to external PSTN numbers.
What is the default configuration of a CAS T1 trunk on the USN?
The default configuration is: E&M, Wink Start, DTMF, DNIS and No ANI.
What is the default configuration of an ISDN T1 trunk on USN?
The default configuration is: NI-2, User Side, DNIS and ANI.
We use an IP PBX system. What interfaces do we need on the USN?
In an all IP environment the USN will interface with the IP PBX over a VoIP/SIP Trunk. The USN will send/receive voice calls towards/from the IP PBX over this interface.
How should the VoIP trunk be configured between the PBX and the USN?
You will need a bi-directional SIP based Tie trunk between the PBX and the USN.
Inbound to USN: Set up a hunt group with number of channels equal to number of VoIP ports on the USN. For example, for a 48 VoIP port system set up a hunt group with 48 channels.
Outbound from USN: Calls originating from USN will be received by the IP PBX which in turn will route them to either internal extensions or to external PSTN numbers. The external connectivity to the PSTN can be via a TDM based T1 trunk or via a VoIP carrier.
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