Goal

To explain what headers need to be present to have an anonymous call routed successfully and explain the correct format.

Product

• Voice

Resolution

In order to send calls anonymously via a CM SIP trunk, the following headers need to be included in the SIP invite:

Privacy: id
This header defines the call to be anonymous. It overrides any information in the ‘FROM’ header, and overrides it with ‘anonymous’, making sure the CLI is not displayed.

P-Asserted Identity (PAID):
This header is used to send a valid CLI with an anonymous call. Without this, a call is not accepted by either CM, or the carrier it is routed to.

Example: P-Asserted-Identity: sip:userpart@hostpart or tel:userpart.

P-Asserted-Identity: sip:[email protected]

Calls with a P-Asserted Identity in non-International number format will be surcharged with €0.25/minute.

A PAID is not mandatory as long as the RPID or From header contains a valid CLI.