For this tutorial we assume that we have two systems in an interconnection. PBX1 with a sip trunk. PBX 2 without any lines. - Of course, this tutorial can be adapted to other configurations.
1.0 Outgoing calls
To be able to dial out with a PBX on an interconnection, which has no defined external line, please follow these points:
- You should create a rule for each possible outgoing digit on "Interconnection -> Location routing", which means, that for an outgoing call the PBX1 line will be selected.
Of course the rule can be adapted to individual needs.
- If not done yet, change the routing of the PBX1 to "line + COR" if you have mor than one line, otherwise "COR" can be chosen.
- Note that you have to create minimum one COR rule in PBX1. It's sufficent to create one for "0".
- The last point to do in PBX1 is to activate "No Screening" for the line, which will be used for outgoing calls.
The next points are to make in PBX2:
- Create in PBX2 a "Dummy" line, which include the real external numbers of the working line of PBX1.
PBX1: line "SIPTrunk", Numbers: 12345 [0-9]
PBX2: line "Dummy", Numbers: 12345 [0-9]
Important: This line was only set up to give the users of PBX2 an external number. So it mustn't have a connection.
- Add the external "dummy" number in PBX2 to the user, which one is allowed to call to external destinations. Make sure that the Display Number is set, too.
Now the User from PBX2 can call external numbers using the line of PBX1.
2.0 Incoming calls
To be reached from an external participant, a group must be created in PBX1 with the external number from PBX1 line "SIPTrunk", and which include only the User from PBX2. Of course the number should be the same like the Display Number from the PBX2 user. The Internal Phone Number isn't necessary, so it can be chosen an uninportant number.
Tip: To keep it clearly, it is recommended, that the group get the same name of the user from PBX2.
Now the user can also be called and called back from external users!