Method and apparatus for transmitting V2X data in wireless communication system

1. A method for transmitting, by a first user equipment (UE), V2X data to a second UE in a wireless communication system, the method comprising:

broadcasting, by the first UE, a Direct Communication Request message;

receiving, in a unicast manner, a Direct Communication Accept message from the second UE receiving the Direct Communication Request message; and

transmitting data of a V2X service to the second UE in a unicast manner,

wherein a source Layer-2 identity (ID) of the first UE included in the broadcast Direct Communication Request message is used by the second UE as a destination Layer-2 ID of the Direct Communication Accept message for unicast reception of the data of the V2X service by the second UE,

wherein the Direct Communication Request message includes information regarding a predetermined number of times and a predetermined interval, and

wherein the Direct Communication Accept message is transmitted based on the second UE receiving the Direct Communication Request message more than the predetermined number of times within the predetermined interval.

2. The method of claim 1 , wherein the Direct Communication Request message comprises information about the V2X service.

3. The method of claim 1 , wherein the Direct Communication Request message is transmitted for establishment of a V2X service oriented layer 2 link.

4. The method of claim 1 , wherein the Direct Communication Accept message corresponds to at least one of a UE that has determined to use the V2X service, a UE that has not determined to use the V2X service but intends to receive data of the V2X service and determine whether to use the V2X service, a UE that has determined to establish an L2 link for the V2X service with the first UE, or a UE that has determined to perform unicast communication with the first UE for the V2X service.

5. A first user equipment (UE) configured to operate in a wireless communication system, the first UE comprising:

a memory; and

at least one processor coupled to the memory,

wherein the at least one processor is configured to, based on executing instructions stored in the memory, control the first UE to:

broadcast a Direct Communication Request message;

receive, in a unicast manner, a Direct Communication Accept message from a second UE receiving the Direct Communication Request message; and

transmit data of a V2X service to the second UE in a unicast manner,

wherein a source Layer-2 identity (ID) of the first UE included in the broadcast Direct Communication Request message is used by the second UE as a destination Layer-2 ID of the Direct Communication Accept message for unicast reception of the data of the V2X service by the second UE

wherein the Direct Communication Request message includes information regarding a predetermined number of times and a predetermined interval, and

wherein the Direct Communication Accept message is transmitted based on the second UE receiving the Direct Communication Request message more than the predetermined number of times within the predetermined interval.

6. The first UE of claim 5 , wherein the Direct Communication Request message comprises information about the V2X service.

7. The first UE of claim 5 , wherein the Direct Communication Request message is transmitted for establishment of a V2X service oriented layer 2 link.

8. The first UE of claim 5 , wherein the Direct Communication Accept message corresponds to at least one of a UE that has determined to use the V2X service, a UE that has not determined to use the V2X service but intends to receive data of the V2X service and determine whether to use the V2X service, a UE that has determined to establish an L2 link for the V2X service with the first UE, or a UE that has determined to perform unicast communication with the first UE for the V2X service.

9. A method for receiving V2X data by a second user equipment (UE) in a wireless communication system, the method comprising:

receiving, by the second UE, a Direct Communication Request message from a first UE in a broadcast manner;

transmitting, by the second UE, a Direct Communication Accept message in a unicast manner; and

receiving data of a V2X service from the first UE in a unicast manner,

wherein a source Layer-2 identity (ID) of the first UE included in the broadcast Direct Communication Request message is used by the second UE as a destination Layer-2 ID of the Direct Communication Accept message for unicast reception of the data of the V2X service by the second UE

wherein the Direct Communication Request message includes information regarding a predetermined number of times and a predetermined interval, and

wherein the Direct Communication Accept message is transmitted based on the second UE receiving the Direct Communication Request message more than the predetermined number of times within the predetermined interval.

10. The method of claim 9 , wherein the Direct Communication Request message comprises information about the V2X service.

11. The method of claim 9 , wherein the Direct Communication Request message is transmitted for establishment of a V2X service oriented layer 2 link.

12. The method of claim 9 , wherein the Direct Communication Accept message corresponds to at least one of a UE that has determined to use the V2X service, a UE that has not determined to use the V2X service but intends to receive data of the V2X service and determine whether to use the V2X service, a UE that has determined to establish an L2 link for the V2X service with the first UE, or a UE that has determined to perform unicast communication with the first UE for the V2X service.

13. A second user equipment (UE) configured to operate in a wireless communication system, the second UE comprising:

a memory; and

at least one processor coupled to the memory,

wherein the at least one processor is configured to, based on executing instructions stored in the memory, control the second UE to:

receive a Direct Communication Request message from a first UE in a broadcast manner;

transmit a Direct Communication Accept message in a unicast manner; and

receive data of a V2X service from the first UE in a unicast manner,

wherein a source Layer-2 identity (ID) of the first UE included in the broadcast Direct Communication Request message is used by the second UE as a destination Layer-2 ID of the Direct Communication Accept message for unicast reception of the data of the V2X service by the second UE

wherein the Direct Communication Request message includes information regarding a predetermined number of times and a predetermined interval, and

wherein the Direct Communication Accept message is transmitted based on the second UE receiving the Direct Communication Request message more than the predetermined number of times within the predetermined interval.