5 Provisioning of parameters for V2X configuration

24.5873GPPProtocol aspectsRelease 16Stage 3TSVehicle-to-Everything (V2X) services in 5G System (5GS)

5.1 General

V2X communication is configured by the use of V2X configuration parameters and their related procedures which allow configuration of necessary V2X configuration parameters.

5.2 Configuration and precedence of V2X configuration parameters

5.2.1 General

UE’s usage of V2X communication is controlled by V2X communication parameters.

The V2X communication parameters consist of the configuration parameters for V2X communication over PC5 and the configuration parameters for V2X communication over Uu.

5.2.2 Precedence of V2X configuration parameters

The V2X configuration parameters can be:

a) pre-configured in the ME;

b) configured in the USIM;

c) provided as a V2XP using the UE policy delivery service as specified in 3GPP TS 24.501 [6] annex D;

d) provided by a V2X application server via V1 reference point; or

e) a combination of case a), b), c) or d) above.

The UE shall use the V2X configuration parameters in the following order of decreasing precedence:

a) the V2X configuration parameters provided as a V2XP using the UE policy delivery service as specified in annex D of 3GPP TS 24.501 [6];

b) the V2X configuration parameters provided by a V2X application server via V1 reference point;

c) the V2X configuration parameters configured in the USIM; and

d) the V2X configuration parameters pre-configured in the ME.

5.2.3 Configuration parameters for V2X communication over PC5

The configuration parameters for V2X communication over PC5 consist of:

a) a validity timer for the validity of the configuration parameters for V2X communication over PC5;

b) a list of PLMNs and RATs in which the UE is authorized to use V2X communication over PC5 when the UE is served by E-UTRA or served by NR. Each entry of the list contains a PLMN ID and RATs in which the UE is authorized to use V2X communication over PC5;

c) an indication of whether the UE is authorized to use V2X communication over PC5 when the UE is not served by E-UTRA and not served by NR;

d) list of RATs in which the UE is authorized to use V2X communication over PC5 and the radio parameters of the RAT for V2X communication over PC5 applicable per geographical area with an indication of whether these radio parameters of the RAT are "operator managed" or "non-operator managed" when the UE is not served by E-UTRA and not served by NR;

e) void

f) optionally, a list of V2X service identifier to PC5 RAT(s) and Tx profiles mapping rules. Each mapping rule contains one or more V2X service identifiers, PC5 RAT(s) and, if the PC5 RAT(s) include E-UTRA-PC5, Tx profiles corresponding to the E-UTRA-PC5;

g) configuration parameters for privacy support, consisting of:

1) a list of V2X services requiring privacy. Each entry of the list contains one or more V2X service identifiers and one or more geographical areas where the privacy is required; and

2) a privacy timer value as specified in 3GPP TS 24.588 [7] clause 5.3;

h) configuration parameters for a V2X communication over PC5 in E-UTRA-PC5, consisting of:

1) a list of V2X service identifier to destination layer-2 ID mapping rules. Each mapping rule contains one or more V2X service identifiers and the destination layer-2 ID;

2) optionally, a default destination layer-2 ID;

3) a list of PPPP to PDB mapping rules. Each mapping rule contains a ProSe Per-Packet Priority (PPPP) and a Packet Delay Budget (PDB);

4) optionally, list of V2X service identifier to V2X E-UTRA frequency mapping rules. Each mapping rule contains one or more V2X service identifiers and the V2X E-UTRA frequencies with associated geographical areas; and

5) optionally, a list of the V2X services authorized for ProSe Per-Packet Reliability (PPPR). Each entry of the list contains one or more V2X service identifiers and a ProSe Per-Packet Reliability (PPPR) value; and

i) configuration parameters for a V2X communication over PC5 in NR-PC5, consisting of:

1) optionally, a list of V2X service identifier to V2X NR frequency mapping rules. Each mapping rule contains one or more V2X service identifiers and the V2X NR frequencies with associated geographical areas;

2) a list of V2X service identifier to destination layer-2 ID for broadcast mapping rules. Each mapping rule contains one or more V2X service identifiers and the destination layer-2 ID for broadcast;

3) optionally, a default destination layer-2 ID for broadcast;

4) a list of V2X service identifier to destination layer-2 ID for groupcast mapping rules. Each mapping rule contains one or more V2X service identifiers and the destination layer-2 ID for groupcast;

5) a list of V2X service identifier to default destination layer-2 ID for unicast initial signaling mapping rules. Each mapping rule contains one or more V2X service identifiers and the default destination layer-2 ID for initial signalling to establish unicast connection;

6) a list of V2X service identifier to PC5 QoS parameters mapping rules. The PC5 QoS parameters are specified in clause 5.4.2 of 3GPP TS 23.287 [3];

7) an AS configuration, including a list of SLRB mapping rules applicable when the UE is not served by E-UTRA and is not served by NR. Each SLRB mapping rule contains a PC5 QoS profile and an SLRB. The PC5 QoS profile contains the following parameters:

i) the PC5 QoS profile contains a PQI;

ii) if the PQI of the PC5 QoS profile identifies a GBR QoS, the PC5 QoS profile contains a PC5 flow bit rates consisting of a guaranteed flow bit rate (GFBR) and a maximum flow bit rate (MFBR);

iii) if the PQI of the PC5 QoS profile identifies a non-GBR QoS, the PC5 QoS profile contains the PC5 link aggregated bit rate consisting of a per link aggregate maximum bit rate (PC5 LINK-AMBR);

NOTE: PC5 link aggregated bit rate is only used for unicast mode communications over PC5.

iv) the PC5 QoS profile contains a range, which is only used for groupcast mode communications over PC5; and

v) the PC5 QoS profile can contain the priority level, the averaging window, and the maximum data burst volume. If one or more of the priority level, the averaging window or the maximum data burst volume are not contained in the PC5 QoS profile, their default values apply;

8) a list of NR-PC5 unicast security policies. Each entry in the list contains an NR-PC5 unicast security policy composed of:

i) one or more V2X service identifiers;

ii) the signalling integrity protection policy for the V2X service identifier(s);

iii) the signalling ciphering policy for the V2X service identifier(s);

iv) the user plane integrity protection policy for the V2X service identifier(s);

v) the user plane ciphering policy for the V2X service identifier(s); and

vi) one or more geographical areas where the NR-PC5 unicast security policy applies; and

9) a list of V2X service identifier to default mode of communication mapping rules. Each mapping rule contains one or more V2X service identifiers and the default mode of communication (one of unicast, groupcast or broadcast).

5.2.4 Configuration parameters for V2X communication over Uu

The configuration parameters for V2X communication over Uu consist of:

a) a validity timer for the validity of the configuration parameters for V2X communication over Uu to 5GCN;

b) optionally, a list of V2X service identifier to PDU session parameters mapping rules. Each mapping rule contains one or more V2X service identifiers of a the V2X service and one or more parameters for establishment of a PDU session for V2X communication over Uu for the V2X services:

1) one of the "IPv4", "IPv6", "IPv4v6" or "Unstructured" PDU session types;

2) an SSC mode;

3) a list of zero or more S-NSSAIs;

4) a list of zero or more DNNs; and

5) one of the UDP or TCP transport layer protocol if the PDU session type is "IPv4", "IPv6" or "IPv4v6"; and

c) a list of PLMNs in which the UE is configured to use V2X communication over Uu. For each PLMN, the list contains:

1) for transfer of a V2X message of a V2X service identified by a V2X service identifier:

i) a list of V2X service identifier to V2X application server address mapping rules, applicable when the UE is registered to the PLMN. Each mapping rule contains:

A) one or more V2X service identifiers;

B) a V2X application server address for unicast consisting of:

– an FQDN, or an IP address; and

– a UDP port for uplink transport, a UDP port for downlink transport, a TCP port for bidirectional transport or any combination of them; and

C) optionally a geographical area; and

ii) optionally, per type of data (IP and non-IP) and V2X message family (in case of non-IP) and optionally a geographical area, one or more default V2X application server addresses for the unicast V2X communication over Uu applicable when the UE is registered to the PLMN. Each V2X application server address consists of:

i) an FQDN, or an IP address; and

ii) a UDP port for uplink transport, a UDP port for downlink transport, a TCP port for bidirectional transport or any combination of them; and

2) for transfer of a V2X message of a V2X service not identified by a V2X service identifier:

i) a list of the V2X application servers per optional geographical area where usage of those V2X application servers applies, applicable when the UE is registered to the PLMN. Each entry of the list contains:

A) a V2X application server address consisting of an FQDN, or an IP address; and

B) optionally, a geographical area.

5.3 Procedures

5.3.1 General

The procedure for provisioning of parameters for V2X configuration allows the UE to obtain information necessary for V2X communication.

5.3.2 UE-requested V2X policy provisioning procedure

5.3.2.1 General

The UE-requested V2X policy provisioning procedure enables the UE to request V2X policy from the PCF in the following cases:

a) if the validity timer for a V2X policy expires; or

b) if there are no valid configuration parameters, e.g., for the current area, or due to abnormal situation.

The UE shall follow the principles of PTI handling for UE policy delivery service procedures defined in 3GPP TS 24.501 [6] clause D.1.2.

5.3.2.2 UE-requested V2X policy provisioning procedure initiation

In order to initiate the UE-requested V2X policy provisioning procedure, the UE shall create a UE POLICY PROVISIONING REQUEST message (see example in figure 5.3.2.2.1). The UE:

a) shall allocate a PTI value currently not used and set the PTI IE to the allocated PTI value;

b) shall include the Requested UE policies IE indicating whether the UE policies for V2X communication over PC5, the UE policies for V2X communication over Uu or both are requested;

c) shall transport the UE POLICY PROVISIONING REQUEST message using the NAS transport procedure as specified in 3GPP TS 24.501 [6] clause 5.4.5; and

d) shall start timer T5040.

Figure 5.3.2.2.1: UE-requested V2X policy provisioning procedure

5.3.2.3 UE-requested V2X policy provisioning procedure accepted by the network

Upon receipt of and accepting the UE POLICY PROVISIONING REQUEST message, the PCF shall create a MANAGE UE POLICY COMMAND message and shall behave as described in clause D.2.1 of 3GPP TS 24.501 [6].

Upon receipt of the MANAGE UE POLICY COMMAND message with the same PTI as included in the UE POLICY PROVISIONING REQUEST message, the UE shall stop timer T5040 and handles the MANAGE UE POLICY COMMAND message as specified in clause D.2.1 of 3GPP TS 24.501 [6].

5.3.2.4 UE-requested V2X policy provisioning procedure not accepted by the network

Upon receipt and rejecting of the UE POLICY PROVISIONING REQUEST message, the PCF shall create a UE POLICY PROVISIONING REJECT message.

The PCF shall set the UPDS cause IE of the UE POLICY PROVISIONING REJECT message to indicate reason for rejecting the UE-requested V2X policy provisioning procedure.

The UPDS cause IE typically indicates one of the following UPDS cause values:

#31 request rejected, unspecified;

#32 service option not supported;

#34 service option temporarily out of order;

#35 PTI already in use; or

#95 – 111 protocol errors.

The PCF shall transport the UE POLICY PROVISIONING REJECT message to the UE via the AMF using the procedure specified in 3GPP TS 23.502 [4].

Upon receipt of the UE POLICY PROVISIONING REJECT message, the UE shall stop timer T5040.

5.3.2.5 Abnormal cases on the network side

The following abnormal cases can be identified:

a) Indication from the lower layer of transmission failure of the UE POLICY PROVISIONING REJECT message.

After receiving an indication from lower layer that the UE POLICY PROVISIONING REJECT message has not been successfully acknowledged (e.g. TCP ACK is not received), the PCF shall abort the procedure.

5.3.2.6 Abnormal cases on the UE

The following abnormal cases can be identified:

a) T5040 expired.

The UE shall, on the first expiry of the timer T5040, retransmit the UE POLICY PROVISIONING REQUEST message and shall reset and start timer T5040. This retransmission is repeated four times, i.e. on the fifth expiry of timer T5040, the UE shall abort the procedure and release the allocated PTI.