Warning About 3CX and Vitelity Trunks

[Greg Beason]

We were about to implement 3CX with Vitelity trunking to replace our Switchvox with Vitelity trunking. We use account based authentication with multiple trunks. Call routing allows us to send different Caller ID which is particularly important for e911 with multiple sites.

I want to make sure no one else is burned by this bug (looks like I'm out my non refundable license and the extra support I just paid for).

According to support,

Kindly note that the system routes the call to the vitelity network and vitelity is responding back with an error message causing the calls not to be successful, we can only comment on the 3CX server.

As per the configuration instructions the template is made for IP-based trunks for vitelity

They are correct when after reviewing the configuration guide. https://www.3cx.com/docs/vitelity-usa-sip-trunk/ I tested Vitelity with a single trunk (free evaluation license) and it worked great using the template. 3CX has a great product, but unfortunately, it is not usable for our needs. Maybe in the future as they have some amazing features.

 

[YiannisH_3CX]

Hello @Greg Beason

Please note that every supported provider has gone through a series of tests based on the provided accounts. In fact specifically with Vitelity we ended up testing the IP based accounts based on what the provider suggested. (Generally we always prefer Register based accounts)
Since you are using a registered based account (I am aware of you ticket) the default template might not work for you since it was created based on tests on a different type of account.
As far as i can see from the captures you provided though, the calls that are being sent out by the PBX are identical. From the first account they work, but Vitelity sends a forbidden message on the second call.
In this case you should ask Vitelity why they are sending the error message. What is it in the Invite they do not like? Why does it work the first time and fails the second?
If they require a change in the outbound parameters they should be able to tell you what it is so we can implement it if possible.

 

[Greg Beason]

This is very strange. I agree.

I'm very glad to see that 3CX is working with me to figure this out. But I did see another member on the forum having the same issue. I hope I didn't come across flaming 3CX. Rather, I don't want anyone seeing the Vitelity working and not catch the IP based requirements.

 

[Greg Beason]

Quick update. Vitelity and 3CX suggested doing separate inbound and outbound trunks. Vitelity likes to have all outgoing communications go to outbound.vitelity.net and inbound based on their different FQDN. A test tonight resulted in the same issue. One trunk allows calls and the other gives a 403 forbidden.

 

[Greg Beason]

Another update.

Technical Support has updated the ticket with the following message:

From the files you have send us again we see that the forbidden message comes from the vitelity IP's, please refer to the attached screenshot. As the setup you have for the specific provider is not tested neither supported by 3CX, then you need to contact the provider in regards to the configuration and troubleshooting any potential issues

I believe this is something under the hood of the 3CX. While SIP is a standard, standards are open to interpretation. Registration based authentication works with Vitelity on Adtrans, Switchvox, Asterisk, and Cisco Call Manager. It just doesn't work with 3CX.

 

[NickD_3CX]

Indeed SIP is a standard, but being someone that has worked with it a lot, I can tell you that SIP is not so clearly defined in the RFCs so a lot of points are "open to interpretation", and unfortunately not everyone perceives this the same way.

Whether it can be made to work or not, this does not change the fact that when 3CX and Vitelity where it talks about the Interoperability between the 2, both agreed to support the IP based method and not the registration-based one. The reasons are not up for debate, but suffice to say both sides agreed to this.
This is also clearly mentioned in the 3CX-Vitelity setup guide: https://www.3cx.com/docs/vitelity-usa-sip-trunk/ (section "Adding IP Endpoints")

I have read the ticket and although there was a best-effort attempt to advise you of a solution, you mentioned it didn't work (separate in and out Trunks).

3CX has a list supported providers and certain registration types for each for exactly these reasons, we can't force people to follow them, but this may happen when you don't.

If some other forum user has experience setting up Vitelity sub-accounts on 3CX, please do PM the OP if you would like to help him.

Other than this though, this topic is being locked, there is nothing more to be discussed.