Forwarding Originator's Caller ID

[HIS-Nhenry]

Good morning all,

I am trying to figure out how to forward originators caller id (caller A) to my end destination. It seems whatever my settings are it will not forward the originators caller id. I have checked with my carrier and all my settings are correct there. Which points to a 3cx setting incorrectly set. This is extremely important as it has to do with 988/chat/text to have the original caller's ID (caller A) to pinpoint where they are. Any and all help is appreciated.

My scenario is two separate 3cx cloud hosted instances, fully up to date.

Caller A calls client Number 1, which then rings a queue, if no answer transfer to our 3cx DID for their queue But when we run a report against the our queue all inbound numbers show Number 1, instead of caller A's called Id.

I have attached some pictures as to how its setup and info if needed.

 

[AbdullaR_3CX]

Hi @HIS-Nhenry
Good morning. This will depend on the SIP provider. Does your provider support CLIP No Screening?
You can check this here under “Clip No Screening Support”:
https://www.3cx.com/partners/sip-trunks

Also, are you using the default 3CX provider template, or a custom/modified template?

 

[HIS-Nhenry]

Yes our sip provider supports Clip No Screening Support with no additional settings to change/enable. (checked with them, didn't assume.) We are using the GenericVoipProvider.pv.xml with no edits/changes to the default settings of the template.

 

[HIS-Nhenry]

The provider is not supported. And I meant using it as is, as in no customizations have been made to the template. I don't think its a sip provider issue. I think it's a 3cx setting that may be set up incorrectly. What would the normal settings on the 3cx side be set to in order to forward originator's caller ID? Because I have changed all the caller ID options under the trunk, and it never seems to change any of the outbound DID caller ID. I guess the only thing I haven't done, is setup a 3cx extension on their system and call every time I make a single change to the caller ID. I figured someone might know what the settings would be to forward originator's caller ID.

 

[AbdullaR_3CX]

First, I would recommend checking with the SIP provider to confirm which SIP field/header they expect the original caller ID in.
For example, if they are using FromUserPart, then the corresponding field in the template should be set to:

<field name="FromUserPart">$OriginatorCallerID</field>

So the first step is to confirm with the provider which field they use, then adjust that field in the template to use $OriginatorCallerID.

You can also refer to our VoIP Provider Template Builder documentation here: https://www.3cx.com/docs/voip-provider-template-builder/

 

[HIS-Nhenry]

Thank you for your assistance. I think its definitely the template configuration. Will make some updates and update tomorrow morning. Thank you for your help!

 

[Guillaume Bourgeois]

Hi,
In North America, even if your SIP provider supports CLIP No Screening, you now generally also need to take an additional step into account: STIR/SHAKEN attestation, based on a signed PASSporT.

It therefore depends heavily on how your SIP provider handles these attestations.

Even with CLIP No Screening, some providers may refuse to pass the original Caller ID when it isn’t recognized or when it doesn’t qualify for an Attestation A or B.

In summary:

• Attestation A: generally, a subscriber call using a Caller ID that matches a DID belonging to that subscriber.
• Attestation B: generally, a verified Caller ID, but the Caller ID doesn’t match a DID directly belonging to that subscriber.
• Attestation C: the source of the call can’t be authenticated.

Some providers may still allow the original Caller ID to pass with an Attestation C, or sometimes without a usable STIR/SHAKEN attestation.

In that case, you also need to consider the provider serving the called party. That provider can apply its own filtering policies and may consider a call with a weak or missing attestation as potentially suspicious or spam, and potentially block that incoming call. This behavior isn’t necessarily systematic and depends on each carrier’s policies.

In summary, in North America, CLIP No Screening, meaning presenting a Caller ID that isn’t directly assigned to the trunk, now requires real coordination with the SIP provider. RFC9060

Ideally, the goal is to make sure that forwarded-call Caller IDs or Caller IDs for outbound calls can receive an Attestation A or B, in order to reduce the risk of filtering, spam labeling, or blocking by the terminating network (or terminating PhoneSystem).

I can’t comment on how this is handled on other continents, since STIR/SHAKEN mechanisms and deployment levels may be different.