System Architecture Evolution
System Architecture Evolution (aka SAE) is the core network architecture of 3GPP's future LTE wireless communication standard.
SAE is the evolution of the GPRS Core Network, with some differences:
- simplified architecture
- All IP Network (AIPN)
- support for higher throughput and lower latency RATs
- support for multiple, heterogeneous RATs, including legacy systems as GPRS, but also non-3GPP systems (say WiMAX)
SAE Architecture
The main component of the SAE architecture is the Evolved Packet Core (EPC), also known as SAE Core, SAE Gateway, and SAE PDU Gateway. The EPC will serve as GGSN for GPRS networks (via the 3GPP Anchor subcomponent), as the equivalent of SGSN and GGSN for the new LTE networks (via the 3GPP Anchor and MME and UPE subcomponents), and as a generic controller for non-3GPP network (via the SAE Anchor subcomponent).
The subcomponents of the EPC are:
- MME (Mobility Management Entity): manages the control plane context, authentication, and authorization
- UPE (User Plane Entity): manages user contexts, ciphering, mobility, and packet routing and forwarding
- 3GPP anchor: manages mobility for legacy (2G/3G) and LTE systems
- SAE anchor: manages mobility for non 3GPP RATs