Last modified at 11/2/2013 11:52 AM by Koen Zomers
3CX PBX v9 offers the ability to bridge two or more 3CX PBX servers. This allows for example branch offices to have their own 3CX PBX installation and be able to connect to the main office 3CX PBX. This allows local calls in the branch office to not use up precious WAN brandwidth. When hooking up two 3CX PBX servers using a bridge, I noticed when somebody calls from an extension on 3CX PBX server A to an extension on 3CX PBX server B, the extension caller id is not being provided to the receiver of the call on the other server. Instead the caller id will show the Authentication ID the 3CX PBX server B uses to connect to 3CX PBX server A thus not identifying the exact caller.

I have not found a solution yet to fix this for all extensions, however, I have found a workaround to fix this on a per extension base:

  1. Connect to the 3CX Phone System management of the server which has the extension you want to fix the caller id for. This may either be done through the webinterface or the management console.
  2. Once logged in, in the 3CX Phone System tree at the left, go to Extensions and browse to the extension you want to fix
  3. On the Other tab of the extension details, enter the desired caller id to be shown to the receiving party in the Outbound Caller ID field

  4. Click OK to apply the changes and close the settings

Now when extension 60 on server B in this sample calls extension 12 which is connected to bridged server A, extension 12 will see 60 as the caller id instead of the bridge authentication id. It isn't a very charming way to achieve this, but it works.