Sip trunking with another pbx

[Hugo_Sycom]

Hello everyone,
I’m trying to connect another pbx 3rd party with my 3cx over a basic SIP trunk. To do that i uses a generic SIP trunk and use no registration but IP based connection. I m able to achieve this goal and place internal calls between both pbx.

Now my next goal would be, my 3CX has a pstn SIP trunk, and i would like be able to call from my other 3rd party pbx over the 3CX to reach pstn network, no clue how to do and if it’s possible.

As far i understood incoming calls to the SIP trunk of the 3cx nees to map an existing DID present on the DID plan(logic). But is there a way to set a default route like « if incoming call from trunk internal with prefix 0 then send the call to trunk pstn and callee value is the same as received on trunk internal »?

I hope you understand what i try to explain

Br hugo

 

[NicholasP_3CX]

You would need to create an outbound rule with the prefixes dialled form the other PBX.

Do not limit the rule to a department or specific extensions. Just use the rules with a prefix, or number length.

 

[Hugo_Sycom]

HI Nicholas,
thank you for your reply, sorry for my delayed reaction, many other projects ongoing.
i'm still not able to perform this interconnection.
i did it as you wrote, but the only thing i reached is the default destination set on my internal trunk... am i missing something?

scenario:
3CX pbx has
- a SIP trunk named "trunk_provider" to reach the provider network
- an outbound route named "outgoing_provider" with +,1 to take this trunk and dial out without any special rules (append prepend ...)
- external calls from internal extensions from 3CX works fine.

then 3CX has a 2nd SIP trunk "named trunk_internal". he is IP based only and communicate with the IP of the other legacy PBX
- From legacy PBX i dial normally 4xx and calls are sent to 3CX, then on "trunk_internal" i did a DDI list to map 4xx dialed number to 3CX internal extensions, and it works.
- but when i dial 0xxxxxxxx from my legacy PBX, the SIP INVITE is sent correctly to the 3CX but i land on the default destination of "trunk_internal" because i guess the 0xxxxxx is not part of the DDI plan of Trunk_internal

so the question, what should i set to trigger on trunk internal, "if you don't find it on your DDI list, send it out via outbound route "outgoing_provider"?

i hope its not too confuse, let me know, thnaks for your help
BR
hugo

 

[leejor]

You might want to consider using a Bridge Trunk between the PBXs. Although it is no longer supported to non-3CX PBXs, it should work, and is/was intended to do what you are attempting.

Here is an archived link to the original 3CX post about bridging to another PBX. Although it was written for an older 3CX version, the same principles apply. As I said, this is no longer officially supported by 3CX.

https://web.archive.org/web/20161213151353/http://www.3cx.com/docs/bridging-asterisk-pbx/