A very Basic question

timaz

Hi all;

 

our office uses traditional PBX system for phone calls and has 2 different gateways (or firewalls) to communicate with the Internet. so we don't have any IP phone structure inside the office. but I've installed CUCM on a test server to learn the basics and have got 2 Cisco IP phones for this too. I wonder if it is possible to configure the CUCM in a way that I can use IP phones to make calls to the PSTN through our PBX system? (none of the gateways have voice-related configurations and hardwares installed on them like FXO ports, E1, etc.)

 

thanks.

bdono26

If PBX supports it, you could configure a SIP trunk from CUCM to PBX.  Otherwise you need a gateway with VWIC card and would have to configure a PRI or a QSIG trunk between the PBX and Cisco gateway.

timaz

If PBX supports it, you could configure a SIP trunk from CUCM to PBX.  Otherwise you need a gateway with VWIC card and would have to configure a PRI or a QSIG trunk between the PBX and Cisco gateway.

 

fortunately I talked to the PBX operator and he said our PBX supports SIP trunks. thanks for your answer [;)]

Remi

Hi Timaz,

 

Indeed, the first step is to connect your CUCM to your legacy PBX (either through QSIG, or H.323/SIP trunk depending on what is supported on the other side).

The second step is the creation of route patterns pointing to the GW/trunk leading to the legacy PBX.

Then, you also have to think about digit manipulation...

 

Rémi