System Architecture Evolution (SAE) is the evolution of the GPRS Core Network and is the core network architecture of 3GPP's LTE wireless communication standard.
SAE has a flat, all-IP architecture with separation of control plane and user plane traffic. The main component of the SAE architecture is the Evolved Packet Core (EPC), also known as SAE Core. The EPC serves as the equivalent of GPRS networks via the Mobility Management Entity, Serving Gateway, and PDN Gateway subcomponents.