Content for  TS 23.288  Word version:  18.4.0

Based on roaming agreements (e.g. SLA), analytics may be exchanged between PLMNs (i.e. HPLMN and VPLMN of a UE served by the NWDAF analytics consumer). In this case, an NWDAF with roaming exchange capability (RE-NWDAF) is used as entry point in a PLMN to exchange analytics in roaming scenario with other PLMNs. It authorizes the analytics request according to roaming agreements, and filters the information exposed to other PLMNs. The roaming architecture is defined in clause 4.3. The H-RE-NWDAF may provide analytics to the V-RE-NWDAF. The V-RE-NWDAF may provide analytics to the H-NWDAF. The H-RE-NWDAF or V-RE-NWDAF provides the Nnwdaf_RoamingAnalytics for that purpose. An RE-NWDAF is the only consumer of these services, i.e. both H-NWDAF and V-NWDAF need to have roaming exchange capability when used as entry point to exchange analytics in roaming scenario. V-RE-NWDAF may request or subscribe to HPLMN analytics from the H-RE-NWDAF as described in clause 6.1.5.2, and then the analytics can be leveraged by the 5GC NF in the VPLMN, for example:

• In home routed roaming scenarios, HPLMN analytics (i.e. slice load level analytics, NF load analytics, etc.) can be leveraged by the AMF in the VPLMN for network slice selection and SMF selection for PDU Session management.
• UE-related analytics (e.g.. service experience analytics, etc.) can include statistics or predictions for outbound roaming UEs.

H-RE-NWDAF may request or subscribe to VPLMN analytics from the V-RE-NWDAF as described in clause 6.1.5.3, and then the analytics can be leveraged by the 5GC NF in the HPLMN, for example:

• In home routed roaming scenarios, analytics information with statistics or predictions for outbound roaming UEs can be leveraged by the H-PCF for QoS control of the PDU Session.
• Analytics (i.e. service experience analytics, slice load level analytics, etc.) can be leveraged by the H-PCF for decision of NSSP in URSP rules provisioned to the UE roaming in the VPLMN.

Figure 6.1.5.2-1 shows the procedure that the V-RE-NWDAF requests network analytics (i.e. slice load level analytics, NF load analytics, service experience analytics, etc.) in HPLMN from a H-RE-NWDAF, upon receiving an analytics information request/subscription from the NF (e.g. AMF) in VPLMN.

Figure 6.1.5.3-1 shows the procedure that the H-RE-NWDAF requests network analytics (i.e. service experience analytics, slice load level analytics, etc.) in VPLMN from the V-RE-NWDAF, upon receiving an analytics information request/subscription from the NF (e.g. PCF) in HPLMN.

When requesting or subscribing to analytics involving one or more roaming UEs, the Consumer NF shall send the request or subscription to an RE-NWDAF belonging to the same PLMN as the Consumer NF. The Consumer NF may indicate the following parameters in the Nnwdaf_AnalyticsInfo_Request or Nnwdaf_AnalyticsSubscription_Subscribe service operation:

• The parameters as defined in clause 6.1.3, with the following differences:
  • Parameters related to analytics aggregation, analytics transfer or ML model selection should not be included;
  • if Target of Analytics Reporting is included and indicates specific UEs or a group of UEs, these UEs shall belong to the same HPLMN (if HPLMN analytics are subscribed/requested) or be served by the same VPLMN (if VPLMN analytics are subscribed/requested)
  • Additionally, the following parameters:
    • If the NWDAF service consumer in a VPLMN requests/subscribes to HPLMN analytics, in Analytics Filter Information:
      • [OPTIONAL] PLMN ID of the HPLMN;
      • [OPTIONAL] mapped S-NSSAI of the HPLMN.
      • [OPTIONAL] AOI (in the form of geographical area) in the HPLMN
    • If the NWDAF service consumer in a HPLMN requests/subscribes to VPLMN analytics, in Analytics Filter Information:
      • [OPTIONAL] PLMN ID of the VPLMN
      • [OPTIONAL] AOI (in the form of geographical area) in the VPLMN

Based on the analytics request or subscription from the NWDAF service consumer in the HPLMN, and local configuration, the H-RE-NWDAF may indicate the following parameters in the Nnwdaf_RoamingAnalytics_Request or Nnwdaf_RoamingAnalytics_Subscribe service operation to the V-RE-NWDAF, for requesting/subscribing to analytics in the VPLMN:

• Analytics ID;
• PLMN ID of the HPLMN;
• Analytics Filter Information:
  • [OPTIONAL] HPLMN S-NSSAI;
  • other Analytics Filter Information (e.g. AOI in the form of geographical area in the VPLMN) as provided by NWDAF service consumer in the HPLMN, if applicable in the VPLMN.
• [OPTIONAL] NF ID(s) of the NF(s) (e.g. AMF(s), SMF(s)) serving the roaming UE(s) in the VPLMN;
• other parameters as provided by NWDAF service consumer in the HPLMN, if applicable in the VPLMN.

Based on the analytics request or subscription from the NWDAF service consumer in the VPLMN, and local configuration, the V-RE-NWDAF may indicate the following parameters in the Nnwdaf_RoamingAnalytics_Request or Nnwdaf_RoamingAnalytics_Subscribe service operation to the H-RE-NWDAF, for requesting/subscribing to analytics in the HPLMN:

• Analytics ID;
• PLMN ID of the VPLMN;
• Analytics Filter Information:
  • [OPTIONAL] HPLMN S-NSSAI;
  • other Analytics Filter Information (e.g. AOI in the form of geographical area in the HPLMN) as provided by NWDAF service consumer in the VPLMN, if applicable in the HPLMN.
• other parameters as provided by NWDAF service consumer in the VPLMN, if applicable in the HPLMN.

The RE-NWDAF provides the following output information to the consumer RE-NWDAF of the Nnwdaf_RoamingAnalytics_Request or Nnwdaf_RoamingAnalytics_Notify service operation:

• The output information as defined in clause 6.1.3, with the following differences:
  • Information related to analytics aggregation (i.e. analytics metadata information) should not be included.