The V2X applications in the present specification, referred to as Vehicle-to-Everything (V2X), contain the following four different types:

• Vehicle-to-Vehicle (V2V)
• Vehicle-to-Infrastructure (V2I)
• Vehicle-to-Network (V2N)
• Vehicle-to-Pedestrian (V2P)

These four types of V2X applications can use "co-operative awareness" to provide more intelligent services for end-users. This means that entities, such as vehicles, roadside infrastructure, application server and pedestrians, can collect knowledge of their local environment (e.g., information received from other vehicles or sensor equipment in proximity) to process and share that knowledge in order to provide more intelligent services, such as cooperative collision warning or autonomous driving. These intelligent transportation services and the associated message sets have been defined in automotive SDOs outside 3GPP. Three basic classes of applications for providing ITS services: road safety, traffic efficiency, and other applications can be found in e.g., [3]. 3GPP only handles the transport of these messages to support different types of V2X applications. The message transport expectations are described in requirements defined in this specification.

V2V applications expect UEs that are in proximity of each other to exchange V2V application information. 3GPP transport of messages containing V2V application information requires the UE to have a valid subscription and authorization from a network operator. Transport for a valid subscriber is provided whether the UE is served or not served by E-UTRAN. The UE supporting V2V applications transmits messages containing V2V application information (e.g. location, dynamics, and attributes). The message payloads may be flexible in order to accommodate varying amount of information. 3GPP transport of message containing V2V application information is predominantly broadcast-based as illustrated in Figure 4.1-2. Such 3GPP transport includes the transport between UEs directly and/or, due to the limited direct communication range, the transport between UEs via infrastructure supporting V2X communication, e.g., RSU, application server, etc.

The UE supporting V2I applications transmits messages containing V2I application information to an RSU or locally relevant application server. The RSU and/or the locally relevant application server transmit messages containing V2I application information to one or more UEs supporting V2I applications. A locally relevant application server serves a particular geographic area. There can be multiple application servers serving overlapping areas, providing the same or different applications.

The UE supporting V2N applications communicates with an application server supporting V2N applications. Both parties communicate with each other via EPS.

V2P applications expect UEs that are in proximity of each other to exchange V2P application information. 3GPP transport of messages containing V2P application information requires the UE to have a valid subscription and authorization from a network operator. Transport for a valid subscriber is provided whether the UE is served or not served by E-UTRAN. The UE supporting V2P applications transmits messages containing V2P application information. It is expected that V2P application information can be transmitted either by a UE supporting V2X application in a vehicle (e.g., warning to pedestrian), or by a UE supporting V2X application associated with a vulnerable road user (e.g., warning to vehicle). 3GPP transport of messages containing V2P application information includes the transport between UEs directly and/or, due to the limited direct communication range, the transport between UEs via infrastructure supporting V2X communication, e.g., RSU, application server, etc.

[R-5.2.1-001] [R-5.2.1-002] [R-5.2.1-003] [R-5.2.1-004] [R-5.2.1-005]

[R-5.2. 2-001] [R-5.2. 2-002]

[R-5.2.3-001]

[R-5.2.4-001]

[R-5.2.5-001] [R-5.2.5-002] [R-5.2.5-003]