Jump to content

SIP trunking using extensions

Carlos Montemayor

Recommended Posts



I just came across a scenario where it would come handy to have a CPE PBX using a sip trunk from a hosted pbx. It seems to be pretty simple and I successfully configured that using a 5.2.2 version for both pbx (the hosted one and the CPE one), however,when I tried to do it with a CPE that is a snom mini version 4.5.1, I could not make it to work. Registration is done with no problems but the calls cannot go through. I am getting a Forbidden message. Everything else is being held the same, I mean, in both scenarios I am using the same final trunk, same phone and same dial plan.


Is there something that I should adjust? Actually, where I really need to do the sip trunking is in the snom mini 4.5.1 (it is with an actual customer), and the CPE with the 5.2.2 version is in my lab (where it worked nicely).





Link to comment
Share on other sites

if your trying to call into the mini the best case scenario is to create an extension on 5.2.2 and register it on the 4.5.1 as a registration trunk and have the call go to an AA, HG or AG you can specify this under the "Destination for incoming calls" under the trunk settings. I personally would use an AA so you can dial any extension on the system.

Link to comment
Share on other sites

Thanks for the prompt response. The scenario is perhaps an easier one. I would like to allow for outbound calls from the mini into the 5.2.2 using a final trunk that is at the 5.2.2. I already created the extension at the 5.2.2 an in the 4.5.1 I created a trunk that registered as that extension in the 5.2.2, however, when calls are made in the 4.5.1 the phones get a "Forbidden" message.

Link to comment
Share on other sites

  • 2 weeks later...

I got it!


It had to do with digit presentation. Once I chose the right combination of "how to rewrite global numbers" and source of caller ID (from, or p-asserted) it started to work fine. I was getting confused because 4.5.1 and 5.2.2 have different presentations of those options.



Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...