LTE RRC Connection and Security Procedures
LTE RRC connection and security procedures define how a UE moves from idle access into protected connected-mode signaling. This hub explains the call flows for RRC connection setup, access rejection, RRC resume, authentication, NAS security activation, initial context setup, UE capability transfer, information transfer, re-establishment, and connection release.
Quick Links
- LTE RRC Connection Setup Procedure
- LTE RRC Connection Reject Procedure
- LTE RRC Resume Procedure
- LTE Authentication Procedure
- LTE NAS Security Procedure
- LTE Security Mode Procedure
- LTE Initial Context Setup Procedure
- LTE UE Capability Transfer Procedure
- LTE DL / UL Information Transfer Procedure
- LTE RRC Re-establishment Procedure
- LTE RRC Connection Release Procedure
What This Covers
LTE RRC connection setup creates the dedicated signaling path used by attach, service request, tracking area update, bearer setup, and mobility procedures.
Security procedures authenticate the UE and activate NAS protection before later EPS signaling continues.
Use the links below to jump directly into setup, reject, resume, authentication, security mode, context setup, capability transfer, re-establishment, and release call flows.
Radio Connection Entry
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.
Authentication and NAS Protection
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.
Context Setup and Control Transfer
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.
Recovery and Re-entry Support
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.