Content for  TS 23.287  Word version:  18.2.0

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5.4.2  PC5 QoS parametersp. 31  PQIp. 31

A PQI is a special 5QI, as defined in clause of TS 23.501, and is used as a reference to PC5 QoS characteristics defined in clause 5.4.3, i.e. parameters that control QoS forwarding treatment for the packets over PC5 reference point.
Standardized PQI values have one-to-one mapping to a standardized combination of PC5 QoS characteristics as specified in Table 5.4.4-1.
Up  PC5 Flow Bit Ratesp. 31

For GBR QoS Flows only, the following additional PC5 QoS parameters exist:
  • Guaranteed Flow Bit Rate (GFBR);
  • Maximum Flow Bit Rate (MFBR).
The GFBR and MFBR as defined in clause of TS 23.501 are used for bit rate control on PC5 reference point over the Averaging Time Window. For PC5 communication, the same GFBR and MFBR are used for both directions.  PC5 Link Aggregated Bit Ratesp. 32

A PC5 unicast link is associated with the following aggregate rate limit QoS parameter:
  • per link Aggregate Maximum Bit Rate (PC5 LINK-AMBR).
The PC5 LINK-AMBR limits the aggregate bit rate that can be expected to be provided across all Non-GBR QoS Flows with a peer UE over PC5 unicast link. The PC5 LINK-AMBR is measured over an AMBR averaging window which is a standardized value. The PC5 LINK-AMBR is not applicable to GBR QoS Flows. PC5 LINK-AMBR is applied to one PC5 unicast link, which means aggregate bit rate of one PC5 unicast link should not exceed PC5 LINK-AMBR.
Up  Rangep. 32

The Range value indicates the applicability of the PC5 QoS parameters in PC5 communication, i.e. when the receiving UEs are not within the Range specified distance from the transmitting UE, the communication is best effort. Lower layer (PHY/MAC layer) may use the Range to determine the corresponding packet handling, e.g. HARQ as defined in TS 38.300, to achieve the QoS guarantee indicated by PC5 QoS parameters.
Range is in the unit of meters. The UE is configured with the maximum Range value it can use for a particular V2X service. A V2X service may request a different range value, and the V2X layer ensures that it does not exceed the maximum Range value.
Range is only used for groupcast mode communication over PC5 reference point.
Up  Default Valuesp. 32

A UE may be configured with default values for PC5 QoS parameters for a particular V2X service type as specified in clause The default value will be used if the corresponding PC5 QoS parameter is not provided by upper layer.

5.4.3  PC5 QoS characteristicsp. 32  Generalp. 32

This clause specifies the PC5 QoS characteristics associated with PQI. The following characteristics defined in TS 23.501 applies, with differences explained in following clauses:
  1. Resource Type (GBR, Delay critical GBR or Non-GBR);
  2. Priority Level;
  3. Packet Delay Budget;
  4. Packet Error Rate;
  5. Averaging window (for GBR and Delay-critical GBR resource type only);
  6. Maximum Data Burst Volume (for Delay-critical GBR resource type only).
Standardized or pre-configured PC5 QoS characteristics, are indicated through the PQI value.
V2X layer may derive non-standardized PC5 QoS characteristics by overriding the standardized or pre-configured value of PC5 QoS characteristics based on V2X Application Requirements from V2X application layer and provide the whole set of non-standardized PC5 QoS characteristics to AS layer.
Up  Resource Typep. 33

Resource Type is defined in clause of TS 23.501.  Priority Levelp. 33

The Priority Level for NR PC5 has the same format and meaning as the Priority value of the ProSe Per-Packet Priority (PPPP) for LTE PC5 defined in TS 23.285. For LTE PC5, the PPPP value also reflects the latency requirement and the PDB derivation is according to TS 23.285, i.e. the low PDB is mapped to the high priority PPPP value. On the other hand, for NR PC5, the PDB is derived from the PQI Table as defined in clause 5.4.4.
The Priority Level shall be used to different treatment of V2X service data across different modes of communication, i.e. broadcast, groupcast, and unicast. In the case when all QoS requirements cannot be fulfilled for all the PC5 service data associated with that PC5 reference point, the Priority Level shall be used to select for which PC5 service data the QoS requirements are prioritized such that a PC5 service data packet with Priority Level value N is prioritized over a PC5 service data packet with higher Priority Level values, i.e. N+1, N+2, etc. (lower number meaning higher priority).
Up  Packet Delay Budgetp. 33

The Packet Delay Budget (PDB) associated with the PQI is equivalent to the PDB defined in clause of TS 23.501. However, when used for PC5 communication, the PDB associated with the PQI defines an upper bound for the time that a packet may be delayed between sending UE and receiving UE(s) over PC5 reference point.  Packet Error Ratep. 33

The Packet Error Rate (PER) is defined in clause of TS 23.501.  Averaging Windowp. 33

The Averaging Window is defined in clause of TS 23.501.  Maximum Data Burst Volumep. 33

Maximum Data Burst Volume (MDBV) is defined in clause of TS 23.501.
MDBV denotes the largest amount of data that the PC5 reference point is required to serve within a period of PDB of the PQI.
The MDBV may also be indicated by upper layer, it shall be used instead of the default value.

5.4.4  Standardized PQI to QoS characteristics mappingp. 33

The one-to-one mapping of standardized PQI values to PC5 QoS characteristics is specified in Table 5.4.4-1.
PQI Value Resource Type Default Priority Level Packet Delay Budget Packet Error Rate Default Maximum Data Burst Volume Default Averaging Window Example Services
(NOTE 1)
320 ms10-4N/A2000 msPlatooning between UEs - Higher degree of automation;
Platooning between UE and RSU - Higher degree of automation
22450 ms10-2N/A2000 msSensor sharing - higher degree of automation
233100 ms10-4N/A2000 msInformation sharing for automated driving - between UEs or UE and RSU - higher degree of automation
55Non-GBR310 ms10-4N/AN/ACooperative lane change - higher degree of automation
56620 ms10-4N/AN/APlatooning informative exchange - low degree of automation;
Platooning - information sharing with RSU
57525 ms10-1N/AN/ACooperative lane change - lower degree of automation
584100 ms10-1N/AN/A Sensor information sharing - lower degree of automation
596500 ms10-2N/AN/APlatooning - reporting to an RSU
90Delay Critical GBR (NOTE 1)310 ms10-42000 bytes2000 msCooperative collision avoidance;
Sensor sharing - Higher degree of automation;
Video sharing - higher degree of automation
9123 ms10-52000 bytes2000 msEmergency trajectory alignment; Sensor sharing - Higher degree of automation
GBR and Delay Critical GBR PQIs can only be used for unicast PC5 communications.

5.4.5  QoS handling for V2X communication over Uu reference pointp. 35  Generalp. 35

The V2X service data can be delivered via Non-GBR QoS Flow as well as GBR QoS Flow (i.e. using the GBR resource type or the Delay-critical GBR resource type) as specified in TS 23.501.
5QI 75 specified in TS 23.501 is intended to be only used for the delivery of V2X messages over MBS.  Notification on QoS Sustainability Analytics to the V2X Application Serverp. 35  Generalp. 35
A V2X Application Server may request notifications on QoS Sustainability Analytics for an indicated geographic area and time interval in order to adjust the application behaviour in advance with potential QoS change. The V2X Application Server may also request past statistical information for the purposes of adjustment of the application, how V2X Application Server makes use of such data is outside of 3GPP scope. Clause 6.4.1 describes the procedure for such notification from 5GS.
Up  Functional descriptionp. 35
The potential QoS change to assist application adjustment is based on the notification of QoS Sustainability Analytics defined in clause 6.9 of TS 23.288. The V2X Application Server acting as an Application Function communicates with the NEF which corresponds to the NF consumer in clause 6.9.4 of TS 23.288.
The V2X Application Server can either subscribe to notifications from the NEF (i.e., a Subscribe-Notify model) or request a single notification from the NEF (i.e. a Request-Response model). The V2X Application Server request contains the following parameters:
  • Analytics ID = "QoS Sustainability";
  • Target of Analytics Reporting: "any UE";
  • Analytics Filter Information:
    • Optional maximum number of objects;
    • QoS requirements:
      • 5QI (standardized or pre-configured), and applicable additional QoS parameters and the corresponding values (conditional, i.e., it is needed for GBR 5QIs to know the GFBR); or
      • the QoS Characteristics attributes including Resource Type, PDB and PER and their values;
    • Location information (the details are specified in clause 6.9.1 of TS 23.288);
    • S-NSSAI (optional, if available in the V2X Application Server).
    • Analytics target period (the details are specified in clause 6.9.1 of TS 23.288);
    • Reporting Threshold(s) (the details are specified in clause 6.9.1 of TS 23.288);
    • In a subscription, the Notification Correlation Id and the Notification Target Address.
Up  QoS Change based on Extended NG-RAN Notification to support Alternative Service Requirementsp. 35

To support V2X applications that can operate with different configurations (e.g. different bitrates or delay requirements), the V2X Application Server (V2X AS), acting as the Application Function, can provide, in addition to the requested level of service requirements, Alternative Service Requirements to the 5GS. This enables the 5GS to act on the Alternative Service Requirements and apply them for the extended NG-RAN notification, as described in TS 23.501 and TS 23.503.
The V2X AS can use the related procedures specified in clause of TS 23.502 to influence the QoS provided to the V2X service. If so, the V2X AS includes Alternative Service Requirements as specified in clause of TS 23.503 when providing service information to the PCF.
The QoS change based on extended NG-RAN notification operates within the 5GS QoS model as specified in TS 23.501 and TS 23.503.

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