CalledNum field not filled on any inbound calls

[mark258]

I'm setting up a PBX for a SIP trunk with a 100-DID number range. The provider is supported.

The problem is that all inbound calls are only routed to the trunk destination that I configured.
The PSTN number is 8-digits, but the called number in the "To:User" field in the SIP INVITE is sent from the provider with the last 3 digits only:

INVITE sip:[email protected]:5060;user=phone SIP/2.0
Max-Forwards: 19
Supported: 100rel
To: <sip:[email protected]>
From: <sip:[email protected]>;tag=xxxxxxxxx
Remote-Party-Id: <sip:[email protected]>;party=calling
Call-ID: [email protected]
CSeq: 1 INVITE
Allow: PUBLISH,MESSAGE,UPDATE,...
Via: SIP/2.0/UDP 10.10.10.10:5060;branch=abcdefg
Contact: <sip:[email protected]:5060>

I've tried all ""CallerNum" caller's number" field mappings, and I've tried various "Reformat Incoming or Outgoing Caller" options without success.

Does 3CX support 3-digit incoming called numbers?

 

[mark258]

Also, if I enable [Use both "Call Source Identification" rules and "Caller Number/Name -> CalledNum" field mappings (Note: Disables catch all routing capability)], then incoming calls are all rejected by the 3CX PBX with "Status: 407 Proxy Authentication Required", verifying that the dialled number is not recognised.

I ran a packet capture and confirmed that the inbound called number is only 3 digits.
The "Main Trunk No" field in the 3CX SIP trunk settings only accepts a minimum of 4-digits, so I could not directly add it as a DID.

I've tried reformatting the number with:
Source: (...) Replace: 0/1
Source: (.*) Replace: 0411 (just as a test, together with adding 0411 as a single DID)

Both of these made no difference, the call was still routed to the main 400 trunk number instead of the 411 DID.

 

[Evolute IT]

I'm setting up a PBX for a SIP trunk with a 100-DID number range. The provider is supported.

The problem is that all inbound calls are only routed to the trunk destination that I configured.
The PSTN number is 8-digits, but the called number in the "To:User" field in the SIP INVITE is sent from the provider with the last 3 digits only:

INVITE sip:[email protected]:5060;user=phone SIP/2.0
Max-Forwards: 19
Supported: 100rel
To: <sip:[email protected]>
From: <sip:[email protected]>;tag=xxxxxxxxx
Remote-Party-Id: <sip:[email protected]>;party=calling
Call-ID: [email protected]
CSeq: 1 INVITE
Allow: PUBLISH,MESSAGE,UPDATE,...
Via: SIP/2.0/UDP 10.10.10.10:5060;branch=abcdefg
Contact: <sip:[email protected]:5060>

I've tried all ""CallerNum" caller's number" field mappings, and I've tried various "Reformat Incoming or Outgoing Caller" options without success.

Does 3CX support 3-digit incoming called numbers?

Who's the provider?

 

[mark258]

Hong Kong Broadband. They’re an IP based provider.

I contacted the first option in the 3CX provider list for my country, and they turned out to be a platinum partner. They suggested I contact the above provider to sign up for a SIP trunk, as that is what they use for their 3CX installs.

 

[cobaltit]

3CX does not support DIDs of less than 4 characters. You have two options:

- Added your DIDs with a * so *NNN
- Talk to the provider (or check the portal if they provide one) to see why they are only sending 3 digits.

 

[mark258]

3CX does not support DIDs of less than 4 characters. You have two options:

- Added your DIDs with a * so *NNN
- Talk to the provider (or check the portal if they provide one) to see why they are only sending 3 digits.

Thanks for the tips, *NNN resolved this issue.
I'll contact the provider to see if they're able to send the full number in future.

 

[YiannisH_3CX]

Hi @mark258

During our testing the provider was sending 4 digit numbers so ask them if they can at least match that and let us know.
Also if your PBX uses a 3 digit extension range make sure your extensions do not overlap with the last 3 digits of your DIDs so you do not run into any issues.