Section: 6.44.2.1 Welcome SMS
Content: The 5G system shall be able to support mechanisms for the HPLMN to provide a notification, including equipment and subscription identifiers, to a trusted application server when a UE successfully registers in a VPLMN. In response to the notification, the trusted application server can indicate specific actions to the HPLMN (e.g., send an SMS to the UE). NOTE: The trusted application server can be hosted by the home operator or a trusted 3rd party and is out of 3GPP scope. 6.44.2.2 Steering of Roaming (SoR) during the registration procedure The 5G system shall be able to support mechanisms enabling the HPLMN to: - provide a notification, including subscription and equipment identifiers, to a trusted application server when a UE tries to register in a VPLMN. - receive a notification reply from the trusted application server indicating specific actions to the HPLMN, e.g., reject UE registration (with a specific cause), trigger a SoR command. NOTE: The trusted application server can be hosted by the home operator or a trusted 3rd party and is out of 3GPP scope.