Application Note: Set SIP Privacy headers when using SIP trunks from multiple operators


When a SOP is configured to use SIP trunks from multiple providers, it might require different SIP Privacy headers to be set, such as the Privacy header and the P-Asserted-Identity header. This documents aims to explain how this can be realized.


Connect to the SMP.


DONE Navigate to:  Communication Routing > Routes

  • If you already have a route going the SIP trunk you can edit it with the values explained below.
  • If you don't : create a new one by clicking on the Add button.
    • Set your telephony route.
    • Select your route group.
    • Select the latest version of MapNumber.


Map Number

On the routes list, look up for the route that you just created and click on MapNumber.

  • Manipulate number : strip all digits
  • Add prefix : select an avaible callflow root extension (in this example *158)
  • Variable : NumberToDial
  • Restriction Group : select one of the restriction groups.


Callflow editor

DONE Navigate to: Communication Flow Studio > Callflow

Add a new call flow by clicking on the Add button.
  • Root Extension : Select the root extension that you have set in the MapNumber configuration (*158 in this example).
  • First Action : Select the latest version of SetVar.


On the callflow list, click on the call flow that you just have created. Edit SetVar action and set the variables
  • SipPrivacyHeader
  • SipPrivateAssertedIdentityNumber

The value of SipPrivacyHeader will be set to the Privacy header, the value of SipPrivateAssertedIdentityNumber will be set to the P-Asserted-Identity. The values are specified by your SIP provider.


Add CallInterfaces >= 1.4 to the next action possible on the callflow.
  • Number to dial : ${NumberToDial} as set in the MapNumber configuration.
  • Interface 1: Name of your SIP trunk.
  • Caller ID policy : As set in Global Parameters.

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