3CX Trunking to Ribbon/AnyNode SBC

[RobP2]

Hi Everyone,

So my experience has always been CUCM and Asterisk / FreePBX distributions, I have a deployment of 3CX however need to connect it to Microsoft Teams.

Normally, you would configure a SIP Trunk on the PBX for the SBC to route calls to and it will pass the signalling and audio setup to the PBX.

So far with 3CX, I have DID's assigned to 1 existing PSTN providers SIP TRUNK, however I wish to be able to create a route plan for that number to forward to another SIP TRUNK being the trunk going to the SBC -> Teams environment.

For the return traffic from Teams, I have tried with a trunk and with a bridge, I am hitting 407 Proxy Auth messages on the SBC side of the Bridge auth however authentication is correct, kind of wondering if anyone else has done this, surely?

The only other alternative is to put my SBC between the 3CX and PSTN carrier then I can drop and insert the calls as I wish but I would really prefer to just pop up anther trunk to 3CX and have it handle the 5 or so extensions which will be in Teams (Meeting rooms)

Any ideas?

Rob

 

[eddv123]

This is going to be a bit of a challenge I would of thought, I have not had the experience of configuring 3CX and teams but have with SBC integration, Audiocodes and most recently Edgewater/Ribbons on prem SBC.

First things first, integration of 3CX with any "professional" SBC is not supported or tested.

SIP Trunk on the PBX for the SBC to route calls to and it will pass the signalling and audio setup to the PBX.

Yes this is similar to what I did, although be aware of some settings on the trunk on 3CX (this guide might help: https://www.3cx.com/docs/sip-trunk-options/

PBX delivers audio - "forces the audio traffic to be redirected through the PBX, which acts as an audio proxy" for gateways and trunks this is normally turned off by default.

Be aware of the settings which control which IP address is being sent to the SBC also, had some real problems with:

"Select which IP to use in 'Contact' (SIP) and 'Connection'(SDP) fields" and " Put Public IP in SIP VIA Header " fields.

What full model of Ribbon SBC are you using ? and does it support transparent mode and/or B2BUA ?

put my SBC between the 3CX and PSTN carrier

More information here, topology diagram would be useful also.

 

[RobP2]

Hi,

So 3CX has a "VOIP Provider" Trunk for a number of PSTN DID's
Extensions are mapped to DID's and route via outbound routes to the "VOIP Provider" Trunk

I would like 3CX to be able to trunk to another standards compliant PBX (SBC) over which I can have a route for specific extension numbers which can then route out via the 3CX "VOIP Provider" trunk.

I suppose I am looking for more granular routing rules within 3CX that I would normally find in Asterisk...

Is there anything in Call Flow to influence routing?

Rob

 

[eddv123]

If you are "bridging" to another PBX, you can use the in built bridging. I have done this to Avaya's and Asterisk in the past myself, for example: https://www.3cx.com/docs/

This will not map inbound numbers (DDI or CID) but require outbound rules to call per bridge. Sounds like you are trying to terminate on an interface on the SBC ? which is uncharted territory for me.
https://www.3cx.com/docs/manual/connecting-pbx-bridges/