Method for transmitting and receiving signals related to PDN connection recovery in wireless communication system, and device therefor

1. A method of transmitting and receiving a signal related to PDN (Packet Data Network) connection recovery, which is transmitted and received by a HSS (Home Subscriber Server) in a wireless communication system, the method comprising:

recognizing, by the HSS, a failure occurred at a PDN connection for an APN (Access Point Name);

determining, by the HSS, whether to change PDN type-related information of the PDN connection for the APN, based on a type of an IP (internet protocol) address registered in an IMS (IP Multimedia Subsystem) network;

transmitting to an MME (Mobility Management Entity), by the HSS, information on a reconfiguration operation of the PDN connection; and

if the PDN type-related information is changed, transmitting the changed PDN type-related information of the PDN connection for the APN to the MME.

2. The method of claim 1 , further comprising:

requesting, by the HSS, PDN type-related information of a PDN connection for an APN to be generated.

3. The method of claim 2 , wherein the request of the PDN type-related information is transmitted to the MME in a manner of being included in Update Location Ack.

4. The method of claim 2 , further comprising:

receiving the generated PDN type-related information of the PDN connection for the APN from the MME.

5. The method of claim 4 , wherein the generated PDN type-related information of the PDN connection for the APN is contained in a Notify request.

6. The method of claim 1 , wherein the PDN type-related information of the PDN connection for the APN corresponds to either a PDN type of PDN connection or a preferred PDN type.

7. The method of claim 1 , wherein if IMS deregistration is received due to an occurrence of an MO (mobile originating) call, the HSS determines to recover the PDN connection for a UE, which has generated the MO call.

8. The method of clam 1 , wherein if a Location info request is received due to an occurrence of an MT (mobile terminating) call, the HSS determines to recover the PDN connection for a UE corresponding to a target of the MT call.

9. The method of claim 1 , wherein if the PDN type of the PDN connection for the APN at which the failure occurs corresponds to IPv6, the changed PDN type of the PDN connection for the APN corresponds to IPv4.

10. A method of transmitting and receiving a signal related to PDN (Packet Data Network) connection recovery, which is transmitted and received by an MME (Mobility Management Entity) in a wireless communication system, the method comprising:

receiving changed PDN type-related information of a PDN connection for an APN (Access Point Name) and receiving information on a reconfiguration operation, from a HSS (Home Subscriber Server), which has recognized a failure occurred at the PDN connection for the APN; and

reconfiguring a PDN connection corresponding to the changed PDN type-related information of the PDN connection of the APN, when the information on the reconfiguration operation is associated with an idle mode of a UE (user equipment) and the UE is in the idle mode.

11. The method of claim 10 , wherein if the reconfigured PDN connection corresponds to a last PDN connection, the MME performs an MME-initiated Detach procedure.

12. The method of claim 11 , wherein the MME-initiated Detach procedure indicates the UE is to perform a re-attach after a detach is performed.

13. The method of claim 10 , wherein if the reconfigured PDN connection does not correspond to a last PDN connection, the MME performs an MME requested PDN disconnection procedure.

14. The method of claim 13 , wherein the MME requested PDN disconnection procedure asks the UE to reactivate a PDN connection for the same APN after PDN disconnection is performed.