Method, apparatus, and system for notifying and learning address information invalidation

A mobile device, comprising at least a processor coupled to a memory which stores program codes, wherein the processor executes the program codes in the memory to configure the mobile device to:

• facilitate a user terminal device's communication to a core network through the mobile device, wherein the user terminal differs in functions from the mobile device;
• receive from the core network, a first notification message which comprises a first default bearer which is both allocated to the mobile device and has already been released by the core network;
• determine address information corresponding to the first default bearer;
• and
• send to the user terminal device, a second notification message which indicates address information invalidation, wherein the second notification message comprises address information invalidation indication information and the address information which corresponds to the first default bearer;
• wherein the second notification message sent from the mobile device causes the user terminal device to delete the received address information corresponding to the first default bearer according to the address information invalidation indication information which is comprised in the second notification message.

A user terminal device, comprising at least a processor coupled to a memory which stores program codes, wherein the processor executes the program codes in the memory to configure the user terminal device to:

• communicate to a core network through a mobile device, wherein the user terminal differs in functions from the mobile device;
• receive a notification message sent by the mobile device, wherein the notification message was previously sent from the core network to the mobile terminal, and the notification message is used to indicate address information invalidation, and wherein the notification message comprises address information invalidation indication information and address information corresponding to a first default bearer, and wherein the first default bearer is a default bearer which is both allocated to the mobile device and has already been released by the core network;
• and
• delete the received address information corresponding to the first default bearer according to the address information invalidation indication information which is comprised in the notification message.