The Radio Resource Control (RRC) layer sits between the upper layers (e.g., PDCP) and the lower layers (e.g., Radio Link Control – RLC) in 5G. It acts as the control center, managing radio resources and establishing connections between the user equipment (UE) and the network. Here are its key tasks:

1. Connection Management: RRC establishes, configures, maintains, and releases radio connections between the UE and the network.
2. Cell Selection and Handover: RRC controls cell selection (choosing the best cell for the UE) and handovers (seamlessly switching UEs between cells) during movement.
3. Radio Resource Configuration: RRC configures various radio resources for the UE, including bandwidth allocation, modulation and coding schemes, and power control settings.
4. Security Management: RRC manages security aspects like ciphering and user authentication to ensure secure communication.
5. Signaling Procedures: RRC handles signaling procedures for various actions, such as paging (alerting the UE for incoming calls), cell registration, and mobility management messages.