5G NAS - Network Slice-Specific Authentication Result

Message Fact Sheet

Protocol	nas	Network	5g
Spec	3GPP TS 24.501	Spec Section	8.2.33
Direction	AMF to UE	Message Type	5GMM signaling

Full message name	5G NAS - Network Slice-Specific Authentication Result
Protocol	NAS
Technology	5G
Direction	AMF to UE
Interface	N1
Signaling bearer / channel	NAS signaling / Dedicated NAS message
Typical trigger	Sent after the network evaluates the UE's slice-specific authentication response.
Main purpose	Tells the UE whether the slice-specific authentication branch completed successfully or failed.
Main specification	3GPP TS 24.501, 8.2.33
Release added	Release 17
Procedures where used	Slice Authentication

What is Network Slice-Specific Authentication Result in simple terms?

Network Slice-Specific Authentication Result is the NAS message carrying the final outcome of slice-specific authentication for a requested S-NSSAI.

Tells the UE whether the slice-specific authentication branch completed successfully or failed.

Why this message matters

This message tells the UE the final extra-authentication outcome for a specific requested slice.

Where this message appears in the call flow

Slice Authentication

Call flow position: Final network result of the slice-specific authentication exchange.

Typical state: UE has already completed the challenge-response step for a requested S-NSSAI.

Preconditions:

The slice-specific authentication response has been evaluated.

Next likely message: Context update via Allowed NSSAI or Rejected NSSAI-related handling

Call flow position

Previous message(s): Network Slice-Specific Authentication Complete

Next message(s): Allowed NSSAI update, Rejected NSSAI handling

Message direction and transport

Sender and receiver: AMF to UE

Interface: N1

Domain: Core-side slicing authorization result signaling

Signaling bearer: NAS signaling

Logical channel: Dedicated NAS message

Transport / encapsulation: NAS 5GS message carried end-to-end between AMF and UE

Security context: Part of the Release 17 slice-specific authentication branch.

Message Structure Overview

This message is the final result of the NSSAA exchange and is best correlated with later Allowed NSSAI or rejected-slice behavior.

ASN.1 Message Syntax for 5G NAS - Network Slice-Specific Authentication Result

This message is not typically analyzed as ASN.1 on the wire. It is usually read as a NAS or protocol field structure instead.

This is a NAS 24.501 message introduced for slice-specific authentication result delivery.

5G NAS - Network Slice-Specific Authentication Result - Example Dump

Network Slice-Specific Authentication Result
  Extended Protocol Discriminator: 5G Mobility Management
  Security Header Type: Integrity protected and ciphered
  Message Type: Network Slice-Specific Authentication Result
  EAP Message: Success

How to read this dump

The result should be correlated with later Allowed NSSAI or rejected-slice handling rather than viewed in isolation.

Important Information Elements

IE	Required	Description
`EAP message`	Yes	Carries the slice-specific authentication result payload.

Detailed field explanation

`EAP message`

Carries the slice-specific authentication result payload.

Presence: Required

In practice: If present, it reflects the external DN authentication result. It is worth checking when the session succeeds on NAS but service access still depends on an external authentication flow.

What to check in logs and traces

Confirm the result belongs to the expected S-NSSAI flow.
Inspect whether the EAP result indicates success or failure.
Check whether Allowed NSSAI or rejected slice context changes afterward.

Common Issues and Troubleshooting

The UE registers successfully but a requested slice remains unavailable.

Likely cause: Slice-specific authentication may have ended in failure or changed the slice authorization result.

What to inspect: Check NSSAA Result together with later Allowed NSSAI and Rejected NSSAI.

Next step: Troubleshoot slice authorization rather than repeating baseline registration analysis.

FAQ

What does Network Slice-Specific Authentication Result do?

It carries the final outcome of slice-specific authentication for the requested network slice.

Related message pages

Related Procedures

Related Tools

Use This Reference in Practice

Decode this message with the 3GPP Decoder, inspect the related message database, or open the matching call flow to see where this signaling step fits in the full procedure.