Content for  TS 23.502  Word version:  19.1.0

NF subscribes to UDM notifications of UE and/or Group Subscription data updates. In the UDM subscription, the NF may request to be notified about expected UE behaviour parameter(s) in Table 4.15.6.3-1 or Application-Specific Expected UE Behaviour parameter(s) in Table 4.15.6.3f-1 or 5G Femto information provisioning parameters in Table 4.15.6.3h-1 that may have been externally provisioned by an AF. If an expected UE behaviour parameter subscription is provided by the NF, the subscription may include a threshold indicating that certain confidence and/or accuracy levels must be met for the parameter(s) to be notified by the UDM to the NF. Meeting the threshold condition may mean that the confidence and/or accuracy levels of a parameter are equal to certain threshold, or less than certain threshold, or greater than certain threshold, or less than or equal to certain threshold, or greater than or equal to certain threshold. The threshold may be in the form of a range (e.g. minimum value to maximum value, where each may be inclusive or exclusive) or a specific value.

[Conditional, on using NWDAF-assisted values] The AF may subscribe to NWDAF via NEF in order to learn the UE mobility analytics and/or UE Communication analytics for a UE or group of UEs by applying the procedure specified in clause 6.1.1.2 of TS 23.288. The Analytics ID is set to any of the values specified in clause 6.7.1 of TS 23.288.

[Conditional, on using NWDAF-assisted values] AF validates the received data and derives any of the Expected UE behaviour parameters defined in clause 4.15.6.3 for a UE or group of UEs.

The AF provides one or more parameter(s) to be created or updated, or deleted in a Nnef_ParameterProvision_Create or Nnef_ParameterProvision_Update or Nnef_ParameterProvision_Delete Request to the NEF. The parameters(s) may include corresponding confidence and/or accuracy levels. The AF provides target UE identifier (e.g. GPSI or External Group ID) as described in clause 5.2.6.4. The Transaction Reference ID identifies the transaction request between NEF and AF. For the case of Nnef_ParameterProvision_Create, The NEF assigns a Transaction Reference ID to the Nnef_ParameterProvision_Create request. NEF checks whether the requestor is allowed to perform the requested service operation by checking requestor's identifier (i.e. AF Identifier). For a Create request associated with a 5G VN group, the External Group ID identifies the 5G VN Group. The payload of the Nnef_ParameterProvision_Update Request includes one or more of the following parameters:

• Expected UE Behaviour parameters (see clause 4.15.6.3); or
• Network Configuration parameters (see clause 4.15.6.3a); or
• 5G VN group data (i.e. 5G VN configuration parameters) (see clause 4.15.6.3b), or
• 5G VN group membership management parameters (see clause 4.15.6.3c); or
• Location Privacy Indication parameters of the "LCS privacy" Data Subset of the Subscription Data (see clause 5.2.3.3.1 of the present document and clause 7.1 of TS 23.273); or
• Ranging/Sidelink Positioning Indication parameters of the "Ranging/Sidelink Positioning privacy" Data Subset of the Subscription Data (see clause 5.2.3.3.1 of the present document and Annex B of TS 33.533); or
• MTC Provider Information; or
• AF provided ECS Address Configuration Information (see clause 4.15.6.3d); or
• DNN and S-NSSAI specific Group Parameters (see clause 4.15.6.3e); or
• Application-Specific Expected UE Behaviour parameters (see clause 4.15.6.3f); or
• 5G Femto information provisioning parameters (see clause 4.15.6.3h); or
• Static IP address assignment parameters (see clause 4.15.6.3i).

The AF may request to delete 5G VN configuration by sending Nnef_ParameterProvision_Delete to the NEF.

If the AF is authorised by the NEF to provision the parameters, the NEF requests to create, update and store, or delete the provisioned parameters as part of the subscriber data via Nudm_ParameterProvision_Create, Nudm_ParameterProvision_Update or Nudm_ParameterProvision_Delete Request message, the message includes the provisioned data and NEF reference ID and optionally MTC Provider Information. If the AF is not authorised to provision the parameters, then the NEF continues in step 6 indicating the reason to failure in Nnef_ParameterProvision_Create/Update/Delete Response message. Step 7 does not apply in this case. If the NEF did not receive DNN and/or S-NSSAI from the AF and such information is configured as needed within 5GC, the NEF determines the DNN and/or S-NSSAI from the AF Identifier. If the AF provides the DNN and S-NSSAI specific Group Parameters, the AF shall indicate the External Group ID, targeted DNN and S-NSSAI in the request. If the AF provides the service area in the form of geographical information, the NEF maps the geographical information to the list of TAs.

UDM may read from UDR, by means of Nudr_DM_Query, corresponding subscription information in order to validate required data updates and authorize these changes for this subscriber or Group for the corresponding AF. Based on local configuration, UDM may determine if there is any requirement in terms of threshold conditions that need to be met by the provisioned parameter before storing the parameter in UDR. If there are no such requirement(s) or the requirement(s) are satisfied, UDM may proceed seamlessly. If not satisfied, step 5 is triggered as a failed procedure and a related cause value is provided, e.g. "confidence level not sufficient". In that case step 4 is skipped.

If the AF is authorised by the UDM to provision the parameters for this subscriber, the UDM resolves the GPSI to SUPI and requests to create, update or delete the provisioned parameters as part of the subscriber data via Nudr_DM_Create/Update/Delete Request message, the message includes the provisioned data. If a new 5G VN group is created, the UDM shall assign a unique Internal Group ID for the 5G VN group and include the newly assigned Internal Group ID in the Nudr_DM_Create Request message. If the list of 5G VN group members is changed or if 5G VN group data has changed, the UDM updates the UE and/or Group subscription data according to the AF/NEF request. When the service area is configured or updated for a group, the UDM authorises the request. If the Default QoS is configured or updated for a group, the UDM authorises the request and uses such Default QoS to set 5GS Subscribed QoS profile in Session Management Subscription data for each UE within the group. The 5GS Subscribed QoS profile in Session Management Subscription data will be considered by SMF as described in clause 5.7.2.7 of TS 23.501. If the Static IP address assignment parameters is created, updated or removed by the AF, the UDM authorises the request and adds, updates or removes such static IP address/prefix in Session Management Subscription data for the UE. The static IP address information in Session Management Subscription data will be considered by SMF as described in clause 5.8.2.2.1 of TS 23.501. UDR stores the provisioned data as part of the UE and/or Group subscription data and responds with Nudr_DM_Create/Update/Delete Response message. If the Maximum Group Data Rate is configured or updated for a 5G VN group, the UDM authorises the request and the Maximum Group Data Rate is applied as described in clause 5.29.2 of TS 23.501. When the 5G VN group data (as described in clause 4.15.6.3b) or 5G VN group membership is updated, the UDR notifies to the subscribed PCF by sending Nudr_DM_Notify as defined in clause 4.16.12.2. If the AF is not authorised to provision the parameters, then the UDM continues in step 5 indicating the reason to failure in Nudm_ParameterProvision_Update Response message and step 7 is not executed. The UDM classifies the received parameters (i.e. Expected UE Behaviour parameters or Suggested Number of Downlink Packets or the 5G VN configuration parameters or DNN and S-NSSAI specific Group Parameters or Location Privacy Indication parameters or ECS Address Configuration Information or Static IP address assignment parameters), into AMF associated and SMF associated parameters. The UDM may use the AF Identifier received from the NEF in step 2 to relate the received parameter with a particular subscribed DNN and/or S-NSSAI. The UDM stores the SMF-Associated parameters under corresponding Session Management Subscription data type. Each parameter or parameter set may be associated with a validity time. The validity time is stored at the UDM/UDR and in each of the NFs, to which parameters are provisioned (e.g. in AMF or SMF). Upon expiration of the validity time, each node deletes the parameters autonomously without explicit signalling. If the ECS Address Configuration Information is provided to any UE in AF request, the UDM shall make use of the shared data mechanism defined in TS 29.503 and notify all NFs (SMFs) that have subscribed to receiving such shared data change notifications.

UDM responds the request with Nudm_ParameterProvision_Create/Update/Delete Response. If the procedure failed, the cause value indicates the reason.

NEF responds the request with Nnef_ParameterProvision_Create/Update/Delete Response. If the procedure failed, the cause value indicates the reason.

[Conditional this step occurs only after successful step 4] UDM notifies the subscribed Network Function of the updated UE and/or Group subscription data via Nudm_SDM_Notification Notify message.

1. If the subscribed NF is AMF, the UDM performs Nudm_SDM_Notification (SUPI or Internal Group Identifier, AMF-Associated Expected UE Behaviour parameters, Subscribed Periodic Registration Timer, subscribed Active Time, 5G VN group data or DNN and S-NSSAI specific Group Parameters, UE allowed CAG list and its validity timer, etc.) service operation. If the AMF receives confidence and/or accuracy levels along the Expected UE behaviour parameter(s), the AMF may use the associated confidence level and/or accuracy level when handling the expected UE behaviour parameter(s). The AMF uses the received parameters to derive the appropriate UE configuration of the NAS parameters and to derive Core Network assisted RAN parameters. The AMF may determine a Registration area based on parameters Stationary indication or Expected UE Moving Trajectory.
   If the AMF obtains service area for a group or SUPI, the AMF configures the DNN for the group as LADN DNN and applies the LADN per DNN and S-NSSAI taking into account the service area for the group as described in clause 5.6.5a of TS 23.501.
2. If the subscribed NF is SMF, the UDM performs Nudm_SDM_Notification (SUPI or Internal Group Identifier, SMF-Associated Expected UE Behaviour parameter set, DNN/S-NSSAI, Suggested Number of Downlink Packets, 5G VN group data, Session Management Subscription data, etc.) service operation.
   The SMF stores the received parameters and associates them with a PDU Session based on the DNN and S-NSSAI included in the message from UDM.
   If the SMF is notified by UDM that the subscription data has changed, and SMF detects that the static IP address/prefix is added, removed or updated, the SMF may perform the PDU Session release procedure and includes a cause value indicating that a PDU Session re-establishment is requested, as described in clause 4.3.4 and in clause 5.8.2.2.1 of TS 23.501.
   If the SMF receives confidence and/or accuracy levels along the Expected UE behaviour parameter(s), the SMF may use the associated confidence level and/or accuracy level when handling the expected UE behaviour parameter(s). The SMF may use the parameters as follows:
   • SMF configures the UPF accordingly. The SMF can use the Scheduled Communication Type parameter or Suggested Number of Downlink Packets parameter to configure the UPF with how many downlink packets to buffer. The SMF may use Communication duration time parameter and/or Expected Inactivity Time parameter and/or Battery Indication parameter combined with their confidence and/or accuracy levels to set the inactivity timer for a PDU Session. The SMF then waits for a UP inactivity report to be received from UPF. Based on the received UP inactivity report, the SMF may determine to deactivate the corresponding UP connection associated to the PDU Session of a single UE or determine a collective pattern of deactivating UP connections for multiple UEs (e.g. for a group of UEs receiving application AI/ML traffic during FL operation) and perform CN-initiated selective deactivation of UP connection of an existing PDU Session.
   • The SMF may derive SMF derived CN assisted RAN information for the PDU Session. The SMF provides the SMF derived CN assisted RAN information to the AMF as described in PDU Session establishment procedure or PDU Session modification procedure.

When setting up the connection between an ASP sponsoring a session and the UE, the ASP may communicate with the AF to request to become the chargeable party for the session to be set up by sending a Nnef_ChargeableParty_Create request message (AF Identifier, UE address, Flow description information or External Application Identifier, Sponsor Information, Sponsoring Status, Background Data Transfer Reference ID, DNN, S-NSSAI) to the NEF. The Sponsoring Status indicates whether sponsoring is started or stopped, i.e. whether the 3rd party service provider is the chargeable party or not. The Background Data Transfer Reference ID parameter identifies a previously negotiated transfer policy for background data transfer as defined in clause 4.16.7. The NEF assigns a Transaction Reference ID to the Nnef_ChargeableParty_Create request.

The NEF authorizes the AF request to sponsor the application traffic and stores the sponsor information together with the AF Identifier and the Transaction Reference ID. If the authorisation is not granted, step 2 is skipped and the NEF replies to the AF with a Result value indicating that the authorisation failed.

The NEF interacts with the PCF by triggering a Npcf_PolicyAuthorization_Create request message and provides IP filter information or Ethernet filter information, sponsored data connectivity information (as defined in TS 23.503), Background Data Transfer Reference ID (if received from the AF) and Sponsoring Status (if received from the AF) to the PCF.

The PCF determines whether the request is allowed and notifies the NEF if the request is not authorized. If the request is not authorized, NEF responds to the AF in step 5 with a Result value indicating that the authorization failed.

The NEF sends a Nnef_ChargeableParty_Create response message (Transaction Reference ID, Result) to the AF. Result indicates whether the request is granted or not.

For the ongoing AF session, the AF may send a Nnef_ChargeableParty_Update request message (AF Identifier, Transaction Reference ID, Sponsoring Status, Background Data Transfer Reference ID) to the NEF. The Sponsoring Status indicates whether sponsoring is enabled or disabled, i.e. whether the 3rd party service provider is the chargeable party or not. The Background Data Transfer Reference ID parameter identifies a previously negotiated transfer policy for background data transfer as defined in clause 4.16.7. The Transaction Reference ID provided in the Change chargeable party request message is set to the Transaction Reference ID that was assigned, by the NEF, to the a Nnef_ChargeableParty_Create request.

The NEF authorizes the AF request of changing the chargeable party. If the authorisation is not granted, step 3 is skipped and the NEF replies to the AF with a Result value indicating that the authorisation failed.

The NEF interacts with the PCF by triggering a Npcf_PolicyAuthorization_Update request and provides IP filter information or Ethernet filter information, sponsored data connectivity information (as defined in TS 23.503), Background Data Transfer Reference ID (if received from the AF) and Sponsoring Status (if received from the AF) to the PCF.

The PCF determines whether the request is allowed and notifies the NEF if the request is not authorized. If the request is not authorized, NEF responds to the AF in step 5 with a Result value indicating that the authorization failed.

The NEF sends a Nnef_ChargeableParty_Update response message (Transaction Reference ID, Result) to the AF. Result indicates whether the request is granted or not.

The AF sends a request to reserve resources for an AF session using Nnef_AFsessionWithQoS_Create request message (UE address, AF Identifier, Flow description information or External Application Identifier, QoS Reference or individual QoS parameters, Alternative Service Requirements (as described in clause 6.1.3.22 of TS 23.503), DNN, S-NSSAI) to the NEF. Optionally, QoS monitoring requirements, Indication of ECN marking for L4S, PDU Set QoS Parameters (as described in clause 5.7.7 of TS 23.501) and Protocol Description (as described in clause 5.37.5 or 5.37.8.3 of TS 23.501) can be included in the AF request. For a Multi-modal service, the AF may provide a Multi-modal Service ID together with Multi-modal Service Requirements information for each data flow, as described in clause 6.1.3.27.3 of TS 23.503. Optionally, a period of time or a traffic volume for the requested QoS can be included in the AF request. The AF may, instead of a QoS Reference, provide one or more of the following individual QoS parameters: Requested 5GS Delay (optional), Requested Priority (optional), Requested Guaranteed Bitrate, Requested Maximum Bitrate, Maximum Burst Size and Requested Packet Error Rate. The AF may also provide an Averaging Window value for deriving such parameters for GBR QoS Flows. Regardless of whether the AF request is formulated using a QoS Reference or individual QoS parameters, the AF may also provide one or more of the following parameters that describe the traffic characteristics: flow direction, Burst Arrival Time at UE (uplink) or UPF (downlink), Periodicity, Time domain, Survival Time, Capability for BAT adaptation or BAT Window, Periodicity Range. The AF may also provide an RT Latency Indication. The optional Alternative Service Requirements provided by the AF shall either contain QoS References or Requested Alternative QoS Parameter Set(s) in a prioritized order as described in clause 6.1.3.22 of TS 23.503. Optionally, Packet Delay Variation requirements can be included in the AF request as described in clause 6.1.3.26 of TS 23.503. Optionally, the AF may provide QoS duration and QoS inactivity interval in order to indicate PCF the time period when the QoS should be applied.

The NEF authorizes the AF request that contains a single UE address and may apply policies to control the overall amount of QoS authorized for the AF. If the authorisation is not granted, all steps (except step 5) are skipped and the NEF replies to the AF with a Result value indicating that the authorisation failed. The NEF assigns a Transaction Reference ID to the Nnef_AFsessionWithQoS_Create request. The NEF determines whether to invoke the TSCTSF or to directly contact the PCF based on operator configuration. This determination may use the presence of a QoS Reference or individual QoS parameters in the AF request. The determination may also use the AF identifier or the presence of AF provided parameters that describe the traffic characteristics in the AF request. If the NEF determines not to invoke the TSCTSF, then steps 3, 4, 5, 6, 7, 8 are executed, otherwise, steps 3a, 3b, 4a, 4b, 5, 6a, 7a, 7b, 8 are executed.

If the NEF determines to contact the PCF directly without invoking the TSCTSF, the NEF uses the UE address to discover the PCF from the BSF. The NEF forwards received parameters to the PCF in the Npcf_PolicyAuthorization_Create request. Any optionally received period of time or traffic volume mapped and forwarded as sponsored data connectivity information (as defined in TS 23.503). If the AF is considered to be trusted by the operator, the AF uses the Npcf_PolicyAuthorization_Create request message to interact directly with PCF to request reserving resources for an AF session.

If the NEF determines to invoke the TSCTSF, the NEF forwards received parameters in the Ntsctsf_QoSandTSCAssistance_Create request message to the TSCTSF. Any optionally received period of time or traffic volume is mapped and forwarded as sponsored data connectivity information (as defined in TS 23.503). If the AF is considered to be trusted by the operator, the AF uses the Ntsctsf_QoSandTSCAssistance_Create request message to interact directly with TSCTSF to request reserving resources for an AF session. A TSCTSF address may be locally configured (a single TSCTSF per DNN/S-NSSAI) in the NEF, PCF and trusted AF. Alternatively, the NEF uses the AF Identifier to determine the DNN/S-NSSAI and uses the DNN/S-NSSAI to discover the TSCTSF from the NRF.

The TSCTSF determines whether it has an AF session with a PCF for the given UE address. In this case the TSCTSF sends a Npcf_PolicyAuthorization_Update request message to the PCF and forwards the received parameters after executing the adjustment and mapping actions described below. If the TSCTSF does not have an AF-session for a given UE address, the TSCTSF discovers the PCF and a Npcf_PolicyAuthorization_Create request message to the PCF. If the TSCTSF receives a Requested 5GS Delay, the TSCTSF calculates a Requested PDB by subtracting the UE-DS-TT Residence Time (either provided by the PCF or pre-configured at TSCTSF) from the Requested 5GS Delay and sends the Requested PDB to the PCF instead of the Requested 5GS Delay. If the TSCTSF receives any of the following parameters: flow direction, Burst Arrival Time, Periodicity, Time domain, Survival Time, Capability for BAT adaptation or BAT Window, Periodicity Range from the NEF, the TSCTSF determines the TSC Assistance Container and sends it to the PCF instead of these parameters.

If the request is authorized, the PCF derives the required QoS parameters of the PCC rule based on the information provided by the NEF and determines whether this QoS is allowed (according to the PCF configuration) and notifies the result to the NEF. If the AF is considered to be trusted by the operator, the PCF sends the Npcf_PolicyAuthorization_Create response message directly to AF. If the PCF receives the individual QoS parameters instead of QoS Reference, the PCF determines a 5QI that matches the individual QoS parameters as described in clause 6.1.3.22 of TS 23.503. It also sets the GBR and MBR for the PCC rule according to the requested values. The PCF may use the Requested Priority from the AF to determine Priority Level as defined in clause 5.7.3.3 of TS 23.501. Requested individual QoS parameter values supersede default values for the 5QI. If the PCF receives the RT Latency Indication described in clause 6.1.3.22 of TS 23.503, the PCF executes Uplink-Downlink Transmission Coordination as described in clause 5.37.7 of TS 23.501 and the associated QoS monitoring for the two correlated QoS Flows as described in clause 6.1.3.27.2 of TS 23.503. If the PCF receives PDU Set QoS parameters described in clause 5.7.7 of TS 23.501, the PDU Set QoS parameters are applied as described in clause 6.1.3.22 of TS 23.503. If the PCF receives an explicit indication (i.e. Indication of ECN marking for L4S) as described in clause 6.1.3.22 of TS 23.503, PCF decides that the service data flow supports ECN marking for L4S. PCF then indicates to the SMF to enable ECN marking for L4S for that QoS flow. In addition, if the Alternative Service Requirements are provided, the PCF derives the Alternative QoS parameter set(s) in the same way from the one or more QoS Reference parameters or the Requested Alternative QoS Parameter Set(s) contained in the Alternative Service Requirements keeping the same prioritized order (as defined in clause 6.1.3.22 of TS 23.503). For multi-modal flows, the PCF derives the required QoS parameters in the PCC rules and generates the QoS monitoring requirements policy for each media flow, based on the information provided by the NEF. If the PCF determines that the SMF needs updated policy information, the PCF issues a Npcf_SMPolicyControl_UpdateNotify request with updated policy information about the PDU Session as described in the PCF initiated SM Policy Association Modification procedure in clause 4.16.5.2.

For requests received from the TSCTSF in step 3b, the PCF determines whether the request is authorized and notifies the TSCTSF if the request is not authorized. If the request is authorized, the PCF derives the required QoS parameters of the PCC rule in the same way it is described in step 4 based on the information provided by the TSCTSF and determines whether this QoS is allowed (according to the PCF configuration) and notifies the result to the TSCTSF. If the PCF determines that the SMF needs updated policy information, the PCF issues a Npcf_SMPolicyControl_UpdateNotify request with updated policy information about the PDU Session as described in the PCF initiated SM Policy Association Modification procedure in clause 4.16.5.2. If the PCF receives a subscription for the 5GS Bridge/Router information from the TSCTSF, if the PCF does not have the 5GS Bridge/Router information for the PDU Session, the PCF uses the PCF initiated SM Policy Association Modification procedure as described in clause 4.16.5.2 to subscribe for 5GS Bridge/Router information event from the SMF. Once the PCF has the 5GS Bridge/Router information, the PCF notifies the TSCTSF for the 5GS Bridge/Router information (including the UE-DS-TT Residence Time).

The TSCTSF sends a Ntsctsf_QoSandTSCAssistance_Create response message (Transaction Reference ID, Result) to the NEF. Result indicates whether the request is granted or not. If the AF is considered to be trusted by the operator, the TSCTSF sends the Ntsctsf_QoSandTSCAssistance_Create response message directly to AF.

The NEF sends a Nnef_AFsessionWithQoS_Create response message (Transaction Reference ID, Result) to the AF. Result indicates whether the request is granted or not.

The NEF shall send a Npcf_PolicyAuthorization_Subscribe message to the PCF to subscribe to notifications of Resource allocation status and may subscribe to other events described in clause 6.1.3.18 of TS 23.503.

The TSCTSF shall send a Npcf_PolicyAuthorization_Subscribe message to the PCF to subscribe to notifications of Resource allocation status and may subscribe to other events described in clause 6.1.3.18 of TS 23.503. The TSCTSF that receives Capability for BAT adaptation or BAT Window in step 3a shall subscribe to notification on BAT offset via sending a Npcf_PolicyAuthorization_Subscribe request message to the PCF.

When the event condition is met, e.g. that the establishment of the transmission resources corresponding to the QoS update succeeded or failed, the PCF sends Npcf_PolicyAuthorization_Notify message to the NEF notifying about the event. If the AF is considered to be trusted by the operator, the PCF sends the Npcf_PolicyAuthorization_Notify message directly to AF.

When the event condition is met, e.g. that the establishment of the transmission resources corresponding to the QoS update succeeded or failed, the PCF sends Npcf_PolicyAuthorization_Notify message to the TSCTSF notifying about the event.

The TSCTSF sends Ntsctsf_QoSandTSCAssistance_Notify message with the event reported by the PCF to the NEF. If the AF is considered to be trusted by the operator, the TSCTSF sends the Ntsctsf_QoSandTSCAssistance_Notify message directly to AF.

The NEF sends Nnef_AFsessionWithQoS_Notify message with the event reported by the PCF to the AF.

For an established AF session with required QoS, the AF may send a Nnef_AFsessionWithQoS_Update request message (AF Identifier, Transaction Reference ID, [Flow description information], [QoS Reference or individual QoS parameters], [Alternative Service Requirements (as described in clause 6.1.3.22 of TS 23.503)]) to NEF for updating the reserved resources. Optionally, Indication of ECN marking for L4S, PDU Set QoS Parameters (as described in clause 5.7.7 of TS 23.501) and Protocol Description (as described in clause 5.37.5 or 5.37.8.3 of TS 23.501) can be included in the AF request. For a Multi-modal service, the AF may provide/update Multi-modal Service Requirements information of the existing data flows as described in clause 6.1.3.27.3 of TS 23.503. Optionally, a period of time or a traffic volume for the requested QoS can be included in the AF request. The Transaction Reference ID provided in the AF session with required QoS update request message is set to the Transaction Reference ID that was assigned, by the NEF, to the Nnef_AFsessionWithQoS_Create request message. The AF may, instead of a QoS Reference, provide one or more of the following individual QoS parameters: Requested 5GS Delay (optional), Requested Priority (optional), Requested Guaranteed Bitrate, Requested Maximum Bitrate, Maximum Burst Size and Requested Packet Error Rate. The AF may also provide an Averaging Window. Regardless whether the AF request is formulated using a QoS Reference or individual QoS parameters, the AF may also provide one or more of the following parameters that describe the traffic characteristics: flow direction, Burst Arrival Time at UE (uplink) or UPF (downlink), Periodicity, Time domain, Survival Time, Capability for BAT adaptation or BAT Window, Periodicity Range. The optional Alternative Service Requirements provided by the AF shall either contain QoS References or Requested Alternative QoS Parameter Set(s) in a prioritized order as specified in clause 6.1.3.22 of TS 23.503. Optionally, Packet Delay Variation requirements can be included in the AF request as described in clause 6.1.3.26 of TS 23.503.

The NEF authorizes the AF request of updating AF session with required QoS and may apply policies to control the overall amount of QoS authorized for the AF. If the authorisation is not granted, all steps (except step 5) are skipped and the NEF replies to the AF with a Result value indicating that the authorisation failed.

The NEF shall contact the same NF type (i.e. TSCTSF or PCF) as with the initial Nnef_AFsessionWithQoS_Create request during the establishment procedure in clause 4.15.6.6. If the NEF determined not to invoke the TSCTSF, then steps 3, 4, 5, 6, 7 are executed, otherwise, steps 3a, 3b, 4a, 4b, 5, 6a, 6b, 7 are executed. If the Nnef_AfsessionWithQoS_Update adds any parameters that would require the NEF to invoke TSCTSF while the NEF determined not to invoke the TSCTSF for the initial Nnef_AFsessionWithQoS_Create request, the NEF shall reject the Nnef_AFsessionWithQoS_Update request with a cause value indicating the reason of failure. If the NEF does not invoke the TSCTSF, the NEF interacts with the PCF by triggering a Npcf_PolicyAuthorization_Update request and forwards received parameters to the PCF. Any optionally received period of time or traffic volume is mapped and forwarded as sponsored data connectivity information (as defined in TS 23.503). If the AF is considered to be trusted by the operator, the AF uses the Npcf_PolicyAuthorization_Update request message to interact directly with PCF to update the reserving resources for an AF session.

If the NEF decided to contact the TSCTSF when the session was established, the NEF forwards received parameters in the Ntsctsf_QoSandTSCAssistance_Update request message to the TSCTSF. Any optionally received period of time or traffic volume is mapped and forwarded as sponsored data connectivity information (as defined in TS 23.503). If the AF is considered to be trusted by the operator, the AF uses the Ntsctsf_QoSandTSCAssistance_Update request message to interact directly with TSCTSF to update the reserving resources for an AF session.

The TSCTSF interacts with the PCF by triggering a Npcf_PolicyAuthorization_Update request and forwards the received parameters after executing the adjustment and mapping actions described in step 3b of clause 4.15.6.6.

The PCF processes the Npcf_PolicyAuthorization_Update request according to the actions described in step 4 of clause 4.15.6.6.

The PCF processes the Npcf_PolicyAuthorization_Update request according to the actions described in step 4a of clause 4.15.6.6. If the PCF has received a request to unsubscribe for 5GS Bridge/Router information Notification, the PCF uses the PCF initiated SM Policy Association Modification procedure as described in clause 4.16.5.2 to unsubscribe for 5GS Bridge/Router information event from the SMF.

The TSCTSF sends a Ntsctsf_QoSandTSCAssistance_Update response message (Transaction Reference ID, Result) to the NEF. Result indicates whether the request is granted or not. If the AF is considered to be trusted by the operator, the TSCTSF sends the Ntsctsf_QoSandTSCAssistance_Update response message directly to AF.

The NEF sends a Nnef_AFsessionWithQoS_Update response message (Transaction Reference ID, Result) to the AF. Result indicates whether the request is granted or not.

The PCF sends Npcf_PolicyAuthorization_Notify message to the NEF when the modification of the transmission resources corresponding to the QoS update succeeded or failed, or when an Alternative Service Requirement is being applied. If the AF is considered to be trusted by the operator, the PCF sends the Npcf_PolicyAuthorization_Notify message directly to AF.

The PCF sends Npcf_PolicyAuthorization_Notify message to the TSCTSF when the modification of the transmission resources corresponding to the QoS update succeeded or failed, or when an Alternative Service Requirement is being applied.

The TSCTSF sends Ntsctsf_QoSandTSCAssistance_Notify message with the event reported by the PCF to the NEF. If the AF is considered to be trusted by the operator, the TSCTSF sends the Ntsctsf_QoSandTSCAssistance_Notify message directly to the AF.

The NEF sends Nnef_AFsessionWithQoS_Notify message with the event reported by the PCF to the AF.