Functional Elements

The architecture consists of the following functionalelements:

Evolved Radio Access Network (RAN)

The evolved RAN for LTE consists of a single node,i.e., the eNodeB (eNB) that interfaces with the UE.The eNB hosts the PHYsical (PHY), Medium AccessControl (MAC), Radio Link Control (RLC), and PacketData Control Protocol (PDCP) layers that includethe functionality of user-plane header-compressionand encryption.

It also offers Radio Resource Control(RRC) functionality corresponding to the controlplane. It performs many functions including radioresource management, admission control, scheduling,enforcement of negotiated UL QoS, cell informationbroadcast, ciphering/deciphering of userand control plane data, and compression/decompressionof DL/UL user plane packet headers.