How about using a media gateway device for inter-connecting a MPLS (Multi Protocol Label Switching) to any virtual PBX system.
Unlike the traditional phone system where in it manually choose a line for outgoing calls, the PBX system on the other hand will automatically select a line for outgoing call. Then, connect the call...
This is the automated attendant service set up in a business phone system that routes incoming calls to extension or department intended for the call.
It is a process of finding suitable person that is capable in handling such call. Or making an schedule for that call to be dialed.
It is a standard feature of many PBXs