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LTE RRC Connection and Security Procedures

This hub groups the LTE procedures that establish the dedicated signaling path and activate the protection needed for later procedure continuation.

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This category covers the radio-side connection step and the security steps that allow later LTE procedures to continue safely.

Common nodes are the UE, eNB, and MME.

These procedures matter because many later failures are actually earlier setup or security breaks.

Procedures that establish or manage the dedicated LTE radio-control connection.

LTE RRC Connection Setup Procedure — Moves the UE from RRC_IDLE into RRC_CONNECTED.
LTE RRC Connection Reject Procedure — Reject path when the eNB does not grant connected access.
LTE RRC Resume Procedure — Restores the signaling context in resume-capable scenarios.

Procedures that authenticate the UE and activate NAS protection before later continuation.

LTE Authentication Procedure — Authenticates the UE before protected continuation.
LTE NAS Security Procedure — Covers NAS protection setup before later messages are protected.
LTE Security Mode Procedure — Activates the selected NAS security state before later continuation.

Procedures that build UE context and carry control information after early access succeeds.

LTE Initial Context Setup Procedure — Establishes UE context after successful access signaling.
LTE UE Capability Transfer Procedure — Transfers UE capability information used for later control decisions.
LTE DL / UL Information Transfer Procedure — Carries later NAS payloads over the RRC path.

Procedures that recover or close the radio-control path after failure or completion.

LTE RRC Re-establishment Procedure — Recovery path after radio link failure or related context loss.
LTE RRC Connection Release Procedure — Releases connected signaling and returns the UE toward idle.