CPC Usage

Calling Party Category (CPC) values identify the type of network or device from which a call originates. CPC information can be delivered either within the SIP URI or in the From header of SIP INVITE messages.

Important

CPC delivery is disabled by default. To enable it, you may need to either configure your SIP trunk manually (see CPC in SIP URI configuration) or request support activation for CPC delivery in the From header (see CPC in From Header).



CPC in a SIP URI

This method delivers the CPC value as part of the SIP URI, allowing you to identify the call source type directly from the request URI.

Note

CPC in SIP URI is supported for Toll-Free numbers only.


CPC Values

The following CPC values indicate the source type of the incoming call:

CPC Value

Source Type

01

Standard landline

02

Mobile network

03

Public payphone

04

Unclassified or unavailable source


SIP URI Format and Examples

The CPC value is appended to the end of the DID before the “@” symbol in the SIP URI.

{DID}{CALL_CPC}@my.domain.com

Examples:

The examples below show how the DID 18003864279 is formatted in SIP URIs, with the last two digits representing the CPC value.

Landline source number: 1800386427901@my.domain.com
Mobile source number:   1800386427902@my.domain.com
Payphone source number: 1800386427903@my.domain.com
Unknown source number:  1800386427904@my.domain.com

SIP Trunk Configuration

To enable this feature, include the {CALL_CPC} variable in the Username field of your SIP trunk configuration.

  1. Navigate to Voice → Inbound Trunks in the User Panel.

  2. Edit an existing inbound SIP trunk.

  3. In the Username field, enter the {CALL_CPC} variable.

  4. Click Submit to save the changes.

Note

  • If you do not have an existing SIP trunk, create a new one.

  • Additional variables such as {DID} or custom symbols can be configured in addition to the {CALL_CPC} variable.

Adding a new SIP Trunk

Fig. 1. Inbound SIP Trunk configuration with {CALL_CPC} variable.



CPC in From Header

This method delivers the CPC value within the From header of the SIP INVITE message, allowing you to identify the call source type directly from SIP signaling. In this case, CPC values are represented in text format, for example: <ordinary>.

Note

CPC delivery in the From header is not enabled by default. To enable this feature for your inbound SIP trunks, please contact support@didww.com .


CPC Values

The following CPC values indicate the source type of the incoming call when included in the From header:

CPC Value

Source Type

<ordinary>

Standard landline

<cellular>

Mobile network

<payphone>

Public payphone

<unknown>

Unclassified or unavailable source


From Header Format and Example

In this configuration, the CPC value is included as a parameter in the SIP From header.

From: <sip:{DID}@your.sip.domain;cpc=value>;tag=12345

Example:

This example shows a call from a standard landline, where the cpc=ordinary parameter identifies the calling party category.

From: <sip:14039351222@46.19.209.14;cpc=ordinary>;tag=12345


Additional Resources

Create a SIP trunk

Create and configure SIP trunks for inbound calls, set transport protocols, authentication, media options, and more.

SIP Trunk
Service Failover and Load Balancing

Understand how to configure trunk groups for failover and load balancing.

Service Failover and Load Balancing