What is RRC and NAS messages?

Radio resource control (RRC) is the highest layer in the control plane of the access stratum (AS) . It also transfers messages of the non-access stratum (NAS), which is located above the RRC layer.5 Eyl 2012

The RRC protocol is the signaling exchanged between the mobile and the evolved Node Base station (eNB) over the LTE-Uu radio interface . The RRC protocol performs the following functions: – Broadcast of system information related to the characteristics of the radio interface.

The major functions of the RRC protocol include connection establishment and release functions , broadcast of system information, radio bearer establishment, reconfiguration and release, RRC connection mobility procedures, paging notification and release and outer loop power control.

The RRC is the highest layer in the control plane of the Access Stratum (AS). The RRC also transfers messages of the Non-Access Stratum (NAS), which is located above the RRC layer. NAS messages are used to control communications between a UE and the Evolved Packet Core (EPC).