LTE Security: Encryption and Integrity Protection Call Flows

These flows describe LTE authentication and NAS / RRC / user-plane ciphering and integrity protection. To verify the security setup in a real capture, VisualEther renders the signaling from a Wireshark PCAP as a sequence diagram, and Claude Code can compare a successful setup against a failed one.

LTE security presentation

Overview of security keys and encryption in LTE. Recommended reading for understanding the following flows.

LTE security call flow

The call flow covers the setup of the NAS, RRC and User Plane security

LTE security overview

A collaboration diagram summarizing the LTE security flow.

UE role

Authentication followed by NAS, RRC and User plane security setup

eNodeB role

RRC and User Plane security setup

MME role

Authentication followed by NAS, RRC and User plane security setup