I have to connect a PBX to Cisco 1861 with CCME. The PBX is a local made and is not having any ports(FXO,FXS,BRI,E1,T1) , instead they have already done the wiring in the entire campus and has terminated it to wall jack. Now i want to know whether its possible to connect a wire from wall jack to Router anc configure with the supported signalling, such that IP Phones connected to the router are able to make calls to other extensions connected to the PBX.
Please help ....
If you plug a regular analog phone (any cheap one will do) into the wall jack and you get dial-tone they are using loopstart signaling, which is the default for an FXO port. Just think of it this way; if you were meant to plug an analog phone into the wall jack, substituting the analog phone for a FXO port on a Cisco gateway is no different from the PBX's perspective.