Method for deactivating ISR capability for proximity service

1. A method in which a user equipment (UE) deactivates an idle mode signaling reduction (ISR) capability for a proximity service concerning direct communication between the UEs, the method comprising:

activating, by the UE, an ISR as a result of performing a routing area update (RAU) procedure or a tracking area update (TAU) procedure;

determining, by the UE, whether to deactivate the ISR for the proximity service; and

deactivating locally the activated ISR on the basis of the determination result,

wherein in the deactivating of the ISR, the ISR is deactivated according to the determination result before an expiration of a timer related to ISR deactivation.

2. The method of claim 1 , wherein the activating of the ISR comprises:

receiving an RAU or TAU accept message; and

activating the ISR on the basis of an ISR activation indication included in the RAU or TAU accept message.

3. The method of claim 1 , wherein the determining of whether to deactivate the ISR comprises one or more of:

determining whether the UE successfully finishes a registration for the proximity service;

determining whether an application of the UE successfully finishes the registration for the proximity service;

determining whether the application of the UE is executed for the proximity service; and

determining whether it is a state in which a network-based discovery is requested or accepted.

4. The method of claim 3 , wherein the determining of whether to deactivate the ISR further comprises one or more of:

confirming whether the capability for the proximity service of the UE exists; and

confirming whether the capability for the proximity service of the UE is in an enable state.

5. The method of claim 1 , further comprising transmitting an RAU or TAU request message after deactivating the ISR.

6. A user equipment (UE) for deactivating an idle mode signaling reduction (ISR) capability for a proximity service concerning direct communication between the UEs, the UE comprises:

a transceiver; and

a processor for controlling the transceiver and for activating an ISR as a result of performing a routing area update (RAU) procedure or a tracking area update (TAU) procedure,

wherein the processor determines whether to deactivate the activated ISR for the proximity service, and deactivates locally the activated ISR according to the determination result and

wherein the processor deactivates the ISR according to the determination result before an expiration of a timer related to ISR deactivation.

7. The UE of claim 6 , wherein when an RAU or TAU accept message is received via the transceiver, the processor activates the ISR on the basis of an ISR activation indication included in the RAU or TAU accept message.

8. The UE of claim 6 , wherein in order to determine whether to deactivate the ISR, the processor performs one or more of:

determining whether the UE successfully finishes a registration for the proximity service;

determining whether an application of the UE successfully finishes the registration for the proximity service;

determining whether the application of the UE is executed for the proximity service; and

determining whether it is a state in which a network-based discovery is requested or accepted.

9. The UE of claim 8 , wherein in order to determine whether to deactivate the ISR, the processor further performs one or more of:

confirming whether the capability for the proximity service of the UE exists; and

confirming whether the capability for the proximity service of the UE is in an enable state.

10. The UE of claim 6 , wherein the processor controls the transceiver to transmit an RAU or TAU request message after deactivating the ISR.