Method for transmitting/receiving V2X message in local network in wireless communication system and apparatus for same

1. A method for transmitting and receiving a vehicle to everything (V2X) message by a user equipment (UE) in a wireless communication system, the method comprising:

transmitting and receiving a V2X message via a long term evolution (LTE) Uu interface of a first local network;

receiving local network boundary-related information from a first base station (BS) of the first local network; and

determining to perform one or more of V2X message transmission or V2X message reception via a PC5 interface during a selected IP traffic offload at local network (SIPTO) period on the basis of the local network boundary-related information.

2. The method according to claim 1 , further comprising, if it is determined to perform one or more of V2X message transmission or V2X message reception via the PC5 interface, performing one or more of V2X message transmission to a road side unit (RSU) or V2X message reception from an RSU.

3. The method according to claim 2 , wherein the RSU is fixed between the first local network and the second local network.

4. The method according to claim 3 , wherein the UE omits a one-to-one link setup procedure with the RSU.

5. The method according to claim 2 , wherein when the UE transmits the V2X message to the RSU, the UE sets a message destination to a Layer-2 ID indicating the RSU.

6. The method according to claim 1 , wherein the UE re-configures a PDN connection with the first local network as a PDN connection with a second local network, during the SIPTO period.

7. The method according to claim 1 , wherein the local network boundary-related information includes one or more of information indicating that a BS is at a local network boundary, information indicating that a local network is changed, information indicating that a cell is at the local network boundary, information indicating the presence of an RSU at the local network boundary, ID information about the RSU, or information about a time of conducting direct communication with the RSU.

8. The method according to claim 1 , wherein if the UE does not receive the local network boundary-related information any longer, the UE determines to transmit or receive a V2X message via an LTE Uu interface.

9. The method according to claim 1 , wherein if the SIPTO period has elapsed, the UE determines to transmit or receive a V2X message via an LTE Uu interface.

10. The method according to claim 1 , wherein if the UE receives one or more of information indicating that a BS is not at a local network boundary, information indicating that a local network is not changed, information indicating that a cell is not at the local network boundary, or information indicating the absence of an RSU, the UE determines to transmit or receive a V2X message via an LTE Uu interface.

11. The method according to claim 1 , wherein the SIPTO period is one of a time corresponding to time information about direct communication with an RSU, a time from the reception of the local network boundary-related information to no longer reception of the local network boundary-related information, and a time from the reception of the local network boundary-related information to reception of one or more of information indicating that a BS is not at a local network boundary, information indicating that a local network is not changed, information indicating that a cell is not at the local network boundary, or information indicating the absence of an RSU.

12. The method according to claim 1 , wherein V2X message transmission or V2X message reception via the PC5 interface is determined according to a type of the UE, a type of a V2X message, or a priority level of the V2X message.

13. A user equipment (UE) for transmitting and receiving a vehicle to everything (V2X) message in a wireless communication system, the UE comprising:

a transceiver; and

a processor,

wherein the processor is configured to transmit and receive a V2X message through the transceiver via a long term evolution (LTE) Uu interface of a first local network, to receive local network boundary-related information from a first base station (BS) of the first local network through the transceiver, and to determine to perform one or more of V2X message transmission or V2X message reception via a PC5 interface during a selected IP traffic offload at local network (SIPTO) period on the basis of the local network boundary-related information.