3GPP 24.501 v20.0.0 — the document's own text

5.4.7.2.1 Network slice-specific EAP message reliable transport procedure initiation

Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).

In order to initiate the network slice-specific EAP message reliable transport procedure, the AMF shall create a NETWORK SLICE-SPECIFIC AUTHENTICATION COMMAND message.

The AMF shall set the EAP message IE of the NETWORK SLICE-SPECIFIC AUTHENTICATION COMMAND message to the EAP-request message which is generated by the AMF or provided by the AAA-S via the NSSAAF.

The AMF shall set the S-NSSAI IE of the NETWORK SLICE-SPECIFIC AUTHENTICATION COMMAND message to the HPLMN S-NSSAI or the SNPN S-NSSAI to which the EAP-request message is related.

The AMF shall send the NETWORK SLICE-SPECIFIC AUTHENTICATION COMMAND message and start timer T3575 per S-NSSAI (see example in figure 5.4.7.1.1).

Upon receipt of a NETWORK SLICE-SPECIFIC AUTHENTICATION COMMAND message, the UE shall stop timer T3346 if running. The UE shall pass:

the EAP-request message received in the EAP message IE; and
the HPLMN S-NSSAI or the SNPN S-NSSAI in the S-NSSAI IE;

to the upper layers. Apart from this action, the network slice-specific authentication and authorization procedure is transparent to the 5GMM layer of the UE.