Granted Patent B2

US 12,507,057 · App. 18/107,213 · Granted Dec 23, 2025

Inventor: Kyungjoo Suh (Gyeonggi-do, KR)

Assignee: Samsung Electronics Co., Ltd.

H04W8/06H04W84/042

Abstract

Claims (52)

1 . A method performed by a user equipment (UE) in a wireless communication system, the method comprising:

transmitting, to a first visited public land mobile network (VPLMN), a first registration request message;

receiving, from the first VPLMN, a registration accept message including first roaming information associated with a home public land mobile network (HPLMN);

validating the first roaming information;

transmitting, to the first VPLMN, a service request message for second roaming information, if the first roaming information is not valid;

receiving, from the first VPLMN, a service accept message including the second roaming information;

transmitting, to an access and mobility management function (AMF) of the first VPLMN, a notifying message indicating that the first roaming information is not valid based on the result of the validating;

setting a timer for releasing a protocol data unit (PDU) session with the first VPLMN;

based on the timer, performing a local release for the PDU session with the first VPLMN;

based on the second roaming information, selecting a second VPLMN; and

transmitting, to the second VPLMN, a second registration request message.

2 . The method of claim 1 , wherein the first roaming information includes at least one of mobility information, modified subscription data information, or VPLMN information to be accessed by the UE.

3 . The method of claim 2 , wherein the VPLMN information to be accessed by the UE is determined by the HPLMN.

4 . A method performed by an access and mobility management function (AMF) associated with a first visited public land mobile network (VPLMN) in a wireless communication system, the method comprising:

receiving, from a user equipment (UE), a registration request message;

in response to the registration request message, transmitting, to a home public land mobile network (HPLMN), a request message;

receiving, from the HPLMN, first roaming information;

transmitting, to the UE, a registration accept message including the first roaming information;

receiving, from the UE, a service request message for second roaming information, if the first roaming information is not valid;

transmitting, to the UE, a service accept message including the second roaming information; and

receiving, from the UE, a notifying message indicating that the first roaming information is not valid.

5 . The method of claim 4 , wherein the first roaming information includes at least one of mobility information, modified subscription data information, or VPLMN information to be accessed by the UE.

6 . The method of claim 5 , wherein the VPLMN information to be accessed by the UE is determined by the HPLMN.

7 . The method of claim 4 , further comprising transmitting, to a session management function (SMF) of the first VPLMN, the notifying message.

8 . A user equipment (UE) in a wireless communication system, the UE comprising:

a transceiver; and

a controller configured to:

transmit, to a first visited public land mobile network (VPLMN), a first registration request message,

receive, from the first VPLMN, a registration accept message including first roaming information associated with a home public land mobile network (HPLMN),

validate the first roaming information,

transmit, to the first VPLMN, a service request message for second roaming information, if the first roaming information is not valid,

receive, from the first VPLMN, a service accept message including the second roaming information,

transmit, to an access and mobility management function (AMF) of the first VPLMN, a notifying message indicating that the first roaming information is not valid based on the result of the validating,

set a timer for releasing a protocol data unit (PDU) session with the first VPLMN,

based on the timer, perform a local release for the PDU session with the first VPLMN,

based on the second roaming information, select a second VPLMN, and

transmit, to the second VPLMN, a second registration request message.

9 . The UE of claim 8 , wherein the first roaming information includes at least one of mobility information, modified subscription data information, or VPLMN information to be accessed by the UE.

10 . The UE of claim 9 , wherein the VPLMN information to be accessed by the UE is determined by the HPLMN.

11 . An access and mobility management function (AMF) associated with a first visited public land mobile network (VPLMN) in a wireless communication system, the AMF comprising:

a transceiver; and

a controller configured to:

receive, from a user equipment (UE), a registration request message,

in response to the registration request message, transmit, to a home public land mobile network (HPLMN), a request message,

receive, from the HPLMN, first roaming information,

transmit, to the UE, a registration accept message including the first roaming information,

receive, from the UE, a service request message for second roaming information, if the first roaming information is not valid,

transmit, to the UE, a service accept message including the second roaming information, and

receive, from the UE, a notifying message indicating that the first roaming information is not valid.

12 . The AMF of claim 11 , wherein the first roaming information includes at least one of mobility information, modified subscription data information, or VPLMN information to be accessed by the UE.

13 . The AMF of claim 12 , wherein the VPLMN information to be accessed by the UE is determined by the HPLMN.

14 . The AMF of claim 11 , the controller is further configured to transmit, to a session management function (SMF) of the first VPLMN, the notifying message.

Assignments (1)

Priority Claims (2)

Continuity (1)

References Cited (21)