mobility management entity (SAE) (MME)
The Mobility Management Entity(MME) is used for mobility management of subscriber equipment( UE) in LTE networks. The MME entity is a network component of the Evolved Packet Core( EPC) between the access network and the System Architecture Evolution( SAE).
The MME entityverifies subscriber authorization, manages the location of the mobile device with the TrackingArea( TA), and stores the connection states and security parameters of the subscriber devices. When the tracking area changes, the MME instance receives a tracking area update. As the central network component, the MME instance forms the link between the Evolved Node B( eNB), which is functionally equivalent to the radio base station, and the Home Subscriber Server( HSS), where subscriber data is stored.
The Mobility Management Entity is involved in the activation and deactivation of the carrier signal and selects the Serving Gateway( SGW) for the User Equipment (UE). Among other functions, the MME entity handles Mobility Management( MM) between LTE networks and 2nd generation( 2G) and 3rd generation( 3G) cellular networks.