Section: 20.3.4 Public User Identity
Content: The Public User Identity shall take the form of a SIP URI (see IETF RFC 3261 [26]), and shall have the form "sip:username@domain". The MSC Server enhanced for ICS shall derive the Public User Identity from the subscriber's IMSI. The Public User Identity shall consist of the string "sip:" appended with a username and domain portion equal to the IMSI derived Private User Identity described in clause 20.3.3. An example using the same example IMSI from clause 20.3.3 can be found below: EXAMPLE: "sip:234150999999999@ics.mnc015.mcc234.3gppnetwork.org".