Pass CallerID from one trunk to another

[g.fiszt]

Hey everyone!

I have a Khomp SBC that all my providers are registered in and when we receive a call, it arrives in this equipment and then I forward it to wherever I want. I have 2 PBXs, one is an Asterisk based PBX and the other is the 3CX. Both have a SIP trunk with the Khomp SBC.
Sometimes we receive a call that is routed to the 3CX, answered, but for some internal reason, it needs to be transferred to other area of the company that uses this Asterisk. All of the trunks are SIP and it works just fine.
The problem is that when a person in the asterisk receives a call transferred by the 3CX, it shows the trunk number instead of the phone number of the person who is calling our company.
I've used SNGREP to take a look at the calls and I've noticed that the call arrives in the 3CX extension showing the correct caller id, but when I make the call to transfer it to the asterisk, the original caller ID is "lost" in the SIP package.
Is there a way that I can "forward" this information or maybe if I could create a custom header and put this information there?

 

[YiannisH_3CX]

Hi @g.fiszt

The option "OriginatorCallerID" will retain the original caller ID when transferring a call back out in most call scenarios. Depending on the SIP headers you are using to read the caller ID from in the Asterisk side you should adjust accordingly.

 

[g.fiszt]

Thanks @YiannisH_3CX

It works when I don't have a fixed outbound caller ID set in the outbound route.
In my case I have an outbound caller ID in the asterisk route, in this case I think the only way for this to work is if I remove the outbound caller ID from the route, right?

 

[leejor]

...or create a second route, used only for forwarded calls, that makes use of a different prefix, and is not assigned a fixed caller ID.

 

[YiannisH_3CX]

It works when I don't have a fixed outbound caller ID set in the outbound route.
In my case I have an outbound caller ID in the asterisk route, in this case I think the only way for this to work is if I remove the outbound caller ID from the route, right?

Yes. If you have a caller ID in the outbound rule route, that bypasses everything. You should remove that if you want it to work.