LTE (Long Term Evolution), commonly marketed as 4G LTE, represents the standard for high-speed wireless communication for mobile devices and data terminals. Developed by the 3rd Generation Partnership Project (3GPP), it was designed to provide a significant leap in data rates and capacity compared to its 3G predecessors (UMTS/HSPA).
The Core Architecture of LTE
LTE is based on an "all-IP" flat architecture. Unlike older generations that used circuit switching for voice and packet switching for data, LTE treats everything—including voice—as data packets.
1. E-UTRAN (Evolved Universal Terrestrial Radio Access Network)
This is the radio side of the network. It consists of a single functional entity: the eNodeB (evolved NodeB). The eNodeB is responsible for all radio-related functions, such as radio resource management, admission control, and scheduling.
2. EPC (Evolved Packet Core)
The EPC is the backbone of the system. It is designed to be lean and efficient to reduce latency. Its key components include: