Here is how to manage Caller ID Settings for outbound calls on 2talk SIP Trunks.
To ensure correct outbound caller ID presentation, your PBX must be configured so that the following headers are set in the SIP INVITE message. Additional headers are required when doing 'A party passthrough'. A party passthrough is where the original calling number is displayed to the recipient of a transferred or diverted call - instead of displaying the number forwarding the call.
SIP Peering Trunk
• 'From' URI user: Must be set to the trunk pilot number or a trunk DDI number. This header is the caller ID to be presented to the callee unless overridden by another header.
• P-Asserted-Identity or 'From' URI display name (optional): Can be set to the trunk DDI number originating the call. This header is the caller ID to be presented to the callee and overrides the caller ID specified in the ‘From’ URI user.
SIP Peering Trunk - Additional Headers for A party passthrough on forwards or blind transfers:
• Diversion: Must be set to the number on your trunk that is forwarding the call.
• P-Asserted-Identity or 'From' URI display name: Must be set to the original A party being passed through. This header is the caller ID to be presented to the callee and overrides the caller ID specified in the ‘From’ URI user.
SIP Peering Trunk - A party passthrough example:
Call scenario:
A party 091234567 (Original Caller - Caller ID to display on forwarded call)
B party 037654321 (Called trunk DDI number and number forwarding the call)
C party 0212345678 (Number the call was forwarded to)
Headers for the forwarded call sent to 2talk:
From: <sip:037654321@203.0.113.1>;tag=as1af6bbdc
To: <sip:0212345678@198.51.100.2>
Diversion: <sip:037654321@203.0.113.1>;privacy=off;reason=unconditional;counter=1;screen=no.
P-Asserted-Identity: <sip:091234567@203.0.113.1;user=phone>
Call recipient 0212345678 will see an incoming call from the original caller number 091234567
Registered Trunk
• 'From' URI user: Must be set to the registered trunk pilot number. This header is the caller ID to be presented to the callee unless overridden by another header.
• Authorization user name: Must be set to the registered trunk pilot number.
• P-Asserted-Identity or 'From' URI display name: Can be set to the trunk DDI number originating the call. This header is the caller ID to be presented to the callee and overrides the caller ID specified in the ‘From’ URI user. Requires ‘Enable Outbound Trunk’ to be enabled on the pilot number in the portal.
Registered Trunk - Additional Headers for A party passthrough on forwards or blind transfers:
• Diversion: Must be set to the number on your trunk that is forwarding the call.
• P-Asserted-Identity or 'From' URI display name: Must be set to the original A party being passed through. This header is the caller ID to be presented to the callee and overrides the caller ID specified in the ‘From’ URI user. Requires ‘Enable Outbound Trunk’ to be enabled on the pilot number.
Registered Trunk - Outbound call example:
Call scenario:
Registered pilot number: 039999999
A party 037654321 (Caller - trunk DDI number originating the call)
B party 0212345678 (Callee - number being dialled)
Headers for the call sent to 2talk:
From: <sip:039999999@203.0.113.1>;tag=as1af6bbdc
To: <sip:0212345678@198.51.100.2>
P-Asserted-Identity: <sip:037654321@203.0.113.1;user=phone>
Authorization: ... username="039999999" ... (attenuated in this example)
Call recipient 0212345678 will see an incoming call from the trunk DDI number 037654321.
Registered Trunk - A party passthrough example:
Call scenario:
Registered pilot number: 039999999
A party 091234567 (Original Caller - Caller ID to display on forwarded call)
B party 037654321 (Called trunk DDI number and number forwarding the call)
C party 0212345678 (Number the call was forwarded to)
Headers for the forwarded call sent to 2talk:
From: <sip:039999999@203.0.113.1>;tag=as1af6bbdc
To: <sip:0212345678@198.51.100.2>
Diversion: <sip:037654321@203.0.113.1>;privacy=off;reason=unconditional;counter=1;screen=no.
P-Asserted-Identity: <sip:091234567@203.0.113.1;user=phone>
Authorization: ... username="039999999" ... (attenuated in this example)
Call recipient 0212345678 will see an incoming call from the original caller number 091234567.