6.3.22 NSACF discovery and selection

23.5013GPPRelease 18System architecture for the 5G System (5GS)TS

The NF consumers shall utilise the NRF to discover NSACF instance(s) unless NSACF information is available by other means, e.g. locally configured in NF consumers.

If the NSACF NF consumer is the AMF, the NSACF selection function in the AMF selects an NSACF instance based on the available NSACF instances, which are obtained from the NRF or locally configured in the AMF.

The following factors may be considered by the NF consumer for NSACF selection:

– S-NSSAI(s).

– NSACF Serving Area information. The NSACF service area is related to the location of the NF consumer.

NOTE: Each Serving Area is unique and unambiguously identified.

– NSACF service capabilities:

– Support monitoring and controlling the number of registered UEs per network slice for the network slice that is subject to NSAC.

– Support monitoring and controlling the number of established PDU Sessions per network slice for the network slice that is subject to NSAC.

In the case of delegated discovery and selection in SCP, the NSACF NF consumer shall send all available factors to the SCP.