In my laymen’s view of phone sysetms there are two different ways to connect people together in a call:
Call Bridging: User A dials PBX, PBX dials User B, PBX connects A and B together. This is a standard conference call. The key thing here is that 2 lines of the PBX are used while the call is taking place.
Call Forwarding: User A dials User B, but number is re-routed to some number other than the one listed for User B. This is call forwarding as provided by the phone company.
My question is, can Asterisk provide TRUE call forwarding. That is after making the connection, the Asterisk system no longer has lines tied up in the conversation. It would seem to me this is possible, as service like 411 do this (or maybe they don’t, maybe they just bridge you together). But most information on call forwarding deals with extensions within the office, and forwards to outside numbers consume line resources or so it seems.
Is there Signalling messages that can be sent to the CO to link the lines together? Or is this something only the phone company can do?
Thanks for any information