What is Notification in LTE NAS?
It is the LTE NAS message the network sends to notify the UE about a NAS-side event or condition.
| Protocol | nas | Network | lte |
|---|---|---|---|
| Spec | 3GPP TS 24.301 | Spec Section | Release 18 message definition for Notification |
| Direction | MME to UE | Message Type | EMM signaling |
| Full message name | LTE Notification |
|---|---|
| Protocol | NAS |
| Technology | LTE |
| Direction | MME to UE |
| Interface | N1 over LTE access / S1-MME control path |
| Signaling bearer / channel | NAS signaling / Sent during established NAS context when the network needs to notify the UE about a special NAS-side event. |
| Typical trigger | Triggered when the network needs to signal a NAS event that changes later handling. |
| Main purpose | Signals a NAS event or status condition so the UE can continue the right higher-level procedure or handling branch. |
| Main specification | 3GPP TS 24.301, Release 18 message definition for Notification |
| Release added | Release 13 |
| Procedures where used | Notification handling |
Notification is the LTE NAS message the network sends when it needs to inform the UE about a specific NAS-side event that affects later handling.
Signals a NAS event or status condition so the UE can continue the right higher-level procedure or handling branch.
Notification is the LTE NAS message the network uses to tell the UE that a NAS-side event happened.
Call flow position: Network notification message sent to inform the UE about a NAS-side event.
Typical state: The wider NAS branch continues after the event is communicated.
Preconditions:
Next likely message: Procedure-specific continuation
Previous message(s): Service Accept, EMM Information
Next message(s): Procedure-specific continuation
Security context: Usually protected because it appears in an active NAS context.
Notification
Notification indicator
Read the notification indicator first and then correlate it with the wider NAS branch.
Notification
Protocol discriminator: EPS mobility management
Security header type: Integrity protected and ciphered
Message type: Notification
Notification indicator: event indication
| IE | Required | Description |
|---|---|---|
Notification indicator | Yes | Tells the UE which NAS-side event or condition is being notified. |
Notification indicatorTells the UE which NAS-side event or condition is being notified.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
Likely cause: The network may have inserted Notification to signal an event that changes later handling.
What to inspect: Check the notification indicator and the surrounding NAS branch.
Next step: Treat the message as a procedural hint rather than a bearer or reject outcome.
It is the LTE NAS message the network sends to notify the UE about a NAS-side event or condition.
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.