Section: 5.30.2.5 Network access control
Content: If a UE performs the registration or service request procedure in an SNPN identified by a PLMN ID and a self-assigned NID and there is no subscription for the UE, then the AMF shall reject the UE with an appropriate cause code to temporarily prevent the UE from automatically selecting and registering with the same SNPN. If a UE performs the registration or service request procedure in an SNPN identified by a PLMN ID and a coordinated assigned NID and there is no subscription for the UE, then the AMF shall reject the UE with an appropriate cause code to permanently prevent the UE from automatically selecting and registering with the same SNPN. NOTE: The details of rejection and cause codes is defined in TS 24.501[ Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3 ]  [47]. If a UE performs the registration in an SNPN using credentials from a Credentials Holder (i.e. the CH is the PLMN/SNPN that owns the UE subscription and controls the access) and the Credentials Holder does not authorize the UE to access that specific SNPN due to access authorization based on subscription data or invalid time for accessing an SNPN that provides access to Localized Services, then the UDM, in the Credentials Holder, can reject the UE which results in AMF rejecting the registration request from the UE with an appropriate cause code to prevent the UE from automatically selecting and registering with the same SNPN using credentials from the Credentials Holder as described in TS 24.501[ Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3 ]  [47]. In order to prevent access to SNPNs for authorized UE(s) in the case of network congestion/overload, Unified Access Control information is configured per SNPN (i.e. as part of the subscription information that the UE has for a given SNPN) and provided to the UE as described in TS 24.501[ Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3 ]  [47].