Caller ID not passed through to external mobile

[ZoomTechnologies]

Hi All my client has an After Hours IVR setup with 2 options, Option 1 Transfer to After mobile, Option 2 Leave a voicemail
Issue is with option 1 which is set to Connect to Extension - this extension is then set to forward to mobile, the call then loses the inbound callees caller ID & displays the customers main number.
Then if they miss the call they don't know who to call back, they don't alway leave a message or don't advise their number

How can we get the caller ID to show on the mobile?

 

[JohnS_3CX]

Hi,

This may or may not be doable, because the PBX is effectively making an outbound call to connect the caller with the mobile.

What you are trying to achieve would effectively be making the PBX send a caller ID to the mobile that does not belong to your trunk and your provider will most likely block this.

Ask your provider if they allow this in the first place and you can see how to move forward from there.

 

[NickD_3CX]

Also, if you are looking for a provider that can do this, check our list of supported providers here:
https://www.3cx.com/partners/sip-trunks/

Which ever one you see with with "Clip No Screening Support - Yes" is a possible candidate, but I would confirm with them as some have requirements to enable this feature.

The reason some providers don't do this is because this allows you to spoof some else's number.

 

[mixig]

We moved away and some of our customers also from 3cx to other vendor because our providers (all of them) are supporting original caller id to be transfered to C number if there is diversion header.
It was a must and we tried multiple times to talk with local providers but diversion header was the only solution.

 

[leejor]

If you confirm that your provider, does indeed allow this, there are some outbound trunk settings that may need to be changed. These can vary from provider to provider.

 

[Peter of a Telco]

Your are correct, it stops spoofing. Also, it stops a hack by unscreened outgoing calls relevant to authentication and applies a certainty around call billing as well. Those Service Providers that allow this 'any number OG CLI' feature can open themselves up for these issues and I have seen many a hack attempt take place. The Diversion Header has not been ratified by RFC but the History-Info Header has. Some Service Providers support one or the other or both which is out-of-dialogue, as well as 302 which is in-dialogue. The Telco I work for supports them all although most PBX/SBC systems (in NZ at least) tend to use the Diversion Header which seems to have organically grown in use for some reason. It works a treat though. REFER is another method you would use as an in-dialog PBX Redirection Method for an Answered Call (CT) from the IVR you refer to but I have no idea about the 3CX as I am learning it myself after having helped many a 3CX Engineer integrate to my Telco SIP Trunk world; I stumbled onto this topic when looking for a way to A-Party PassThrough on a CF call; no luck so far. Not much help I know; sorry if I am rambling.