Content for  TS 23.285  Word version:  17.1.0

The E-UTRAN attach procedure for UE is performed as defined in TS 23.401 with the following additions:

• The UE includes the V2X capability indication as part of the "UE Network Capability" in the Attach Request message. The MME stores this information for V2X operation. The V2X capability can indicate whether the UE is capable of supporting V2X communication over PC5 reference point.
• If the UE indicated V2X capability, and the UE is authorized to use V2X communication over PC5 reference point based on the subscription data, then the MME shall include a "V2X services authorized" indication in the S1-AP Initial Context Setup Request, indicating the UE is authorized to use V2X communication over PC5 reference point as Vehicle UE, Pedestrian UE or both.
• The MME obtains the UE-PC5-AMBR from the HSS as part of the subscription data and includes it in the S1-AP Initial Context Setup Request to the eNodeB, which use it in resource management of UE's PC5 transmission for V2X services in network scheduled mode.

The Service Request procedures for UE are performed as defined in TS 23.401 with the following additions:

• If the UE is V2X capable, and the UE is authorized to use V2X communication over PC5 reference point based on the subscription data, then the MME shall include a "V2X services authorized" indication in the S1-AP Initial Context Setup Request, indicating the UE is authorized to use V2X communication over PC5 reference point as Vehicle UE, Pedestrian UE or both.
• The MME includes the UE-PC5-AMBR in the S1-AP Initial Context Setup Request to the eNodeB which stores it as part of the UE context and may use it in resource management of UE's PC5 transmission for V2X services in network scheduled mode.

The Intra-E-UTRAN S1-based handover or the Inter-RAT to E-UTRAN handover procedures for UE are performed as defined in TS 23.401 with the following additions:

• If the UE is V2X capable, and the UE is authorized to use V2X communication over PC5 reference point based on the subscription data, then the target MME shall send the "V2X services authorized" indication and UE-PC5-AMBR to the target eNodeB as follows:
  • For the intra MME handover, the "V2X services authorized" indication and UE-PC5-AMBR are included in the S1-AP Handover Request message. If after the handover procedure, the "V2X services authorized" indication or the UE-PC5-AMBR or both are changed, the updated "V2X services authorized" indication or the updated UE-PC5-AMBR or both are included in the S1-AP UE Context Modification Request message sent to the target eNodeB.
  • For the inter MME handover or Inter-RAT handover to E-UTRAN, the "V2X services authorized" indication and UE-PC5-AMBR are included in the S1-AP UE Context Modification Request message sent to the target eNodeB after the handover procedure.

The "V2X services authorized" indication sent to target eNodeB denotes the UE is authorized to use V2X communication over PC5 reference point as Vehicle UE, Pedestrian UE or both.

For the X2-based handover, the "V2X services authorized" indication and the UE-PC5-AMBR are sent to target eNodeB as follows:

• If the source eNodeB is V2X-enabled and the "V2X services authorized" indication is included in the UE context, then the source eNodeB shall include a "V2X services authorized" indication and UE-PC5-AMBR in the X2-AP Handover Request message to the target eNodeB.
• If the UE is V2X capable, and the UE is authorized to use V2X communication over PC5 reference point based on the subscription data, then the MME shall send the "V2X services authorized" indication and the UE-PC5-AMBR to the target eNodeB in the Path Switch Request Acknowledge message. If, after the handover procedure, the "V2X services authorized" indication or the UE-PC5-AMBR or both are changed, the updated "V2X services authorized" indication or the updated UE-PC5-AMBR or both are included in the S1-AP UE Context Modification Request message sent to the target eNodeB.

The "V2X services authorized" indication sent to target eNodeB denotes the UE is authorized to use V2X communication over PC5 reference point as Vehicle UE, Pedestrian UE or both. The UE-PC5-AMBR is sent to target eNodeB for the resources management of UE's PC5 transmission in V2X communication.

The Tracking Area Update procedures for UE are performed as defined in TS 23.401 with the following additions:

• The UE includes the V2X capability indication as part of the "UE Network Capability" in the Tracking Area Update Request message. The MME stores this information for the V2X operation.
• If the MME determines to re-establish the radio and S1 bearers for all active EPS bearer contexts due to the "active" flag included in the Tracking Area Update Request message or the pending downlink data or signalling, the UE is V2X capable, and the UE is authorized to use V2X communication over PC5 reference point based on the subscription data, then the MME shall include a "V2X services authorized" indication and UE-PC5-AMBR in the S1-AP Initial Context Setup Request. The "V2X services authorized" indication sent to eNodeB denotes the UE is authorized to use V2X communication over PC5 reference point as Vehicle UE, Pedestrian UE or both.

The Insert Subscriber Data procedures for UE are performed as defined in TS 23.401 with the following additions:

• If the "V2X services authorized" indication or the UE-PC5-AMBR or both need to be changed due to the changed subscription data and the S1 bearer is established, then the MME shall notify the eNodeB the updated "V2X services authorized" indication or the UE-PC5-AMBR or both via the S1-AP UE Context Modification Request message.

Delete Subscriber Data procedure for UE is performed as defined in TS 29.272 with the same additions as in clause 5.5.6.

A UE may support multiple PC5 RATs (i.e. LTE PC5 and NR PC5). For such UE, the V2X capability indication for NR PC5 and V2X related information (i.e. "V2X services authorized" indication and UE-PC5-AMBR) described in clause 5.5.1 to clause 5.5.7 is per PC5 RAT.

To support V2X communication over NR PC5 reference point, the EPC procedures described in clause 5.5.1 to clause 5.5.7 are applied with the following differences:

• The PC5 QoS parameters may be included in the S1-AP Initial Context Setup Request, S1-AP Handover Request, S1-AP UE Context Modification Request, X2-AP Handover Request, and Path Switch Request Acknowledge messages.