dialog or added by the device), a Privacy header is added with
the value "id".
[2] Restrict = The user identity is restricted (the restricted
presentation is as mentioned above).
[3] Remove Restriction = The device attempts to reveal the user
identity by setting user values in the From header and removing the
privacy "id" value if the Privacy header exists.
If the From header user is anonymous, the value is taken from the P-
Preferred-Identity, P-Asserted-Identity, or Remote-Party-ID header (if
exists).
The device identifies an incoming user as restricted if one of the
following exists:
From header user is anonymous.
P-Asserted-Identity and Privacy headers contain the value "id".
Note: All restriction logic is performed after the user number has been
manipulated.