How to Integrate Branch Office Phones

I have 2 Asterisk servers set up–one at the main office and one at a branch office. At the moment each office is running as a separate system, though I have set up extension dialing between the two servers. The gateway/router has all the needed ports forwarded to the Asterisk servers.

Here is an image of my current setup:

The problem now is that the receptionist at the main office needs to see who is available/status of all extensions. Right now she can only see extensions of the main office phones but she needs to see the 2nd office as well.

What can I do to get the phones in the 2nd office to actually be part of the main Asterisk server?

Can I just tell them to register to the main server and use something like STUN? I’m afraid I won’t get RTP streams through consistently. Is there any way I can use the Asterisk server at the 2nd office to be a SIP/RTP proxy for the phones at the 2nd office and have them really be extensions of the main office Asterisk box?

I’m just trying to figure out my options.


Anyone have an experience with this? Maybe I should just set static RTP ports for each branch phone and put static port forwarding in the router?


I have a feeling that the latest versions of Asterisk support remote presence.


We have done this on sites, Asternic FOP and FOP2 both support multiple servers, So Both sites have a asterisk server connected via IAX so that you can use “switch” statement .

Works well.