The Mobility Management Entity (MME) plays a vital role in ensuring control plane network in EPC, Tracking Area Updates, Subscriber attach/detach, signaling coordination for SAE Bearer Activation/deActivation, chooses SGW for UE, Authentication with HSS, Assigns temporary identity to UE and so on. Here are the functions of the MME in LTE networks.
Tracking Area Management: The LTE network is divided into tracking areas, which consist of multiple base stations. The MME keeps track of UEs’ current tracking areas and manages the tracking area updates as UEs move across different areas. It ensures that UEs receive incoming calls or messages even when they are in idle mode By managing tracking areas, it enables uninterrupted connectivity as UEs move from one area to another.
User Authentication and Security: The MME authenticates and authorizes user devices when they connect to the network. It ensures that only authorized devices can access the network resources and enforces security measures to protect against unauthorized access.
- Paging and Connection Management: Need to establish a connection with a UE? The MME initiates the paging process, locating the UE and establishing the necessary connection and data bearers.
- Session Management: Ensuring smooth session establishment, modification, and termination is another crucial function of the MME. It handles quality of service QoS parameters and ensures UEs receive the appropriate services based on their subscription and network policies.
- Roaming Support: As UEs roam between networks, the MME facilitates a seamless transition. It performs authentication and authorization procedures, manages handovers, and enables mobility between different networks.
- Interworking with External Networks: The MME ensures smooth mobility and interconnectivity by interacting with external networks, such as the Evolved Packet Core (EPC) and other 4G/3G networks.
The MME is the backbone of mobility and connectivity in 4G networks and it is pure signaling entity inside the EPS. Its efficient management of tracking areas, authentication, connection establishment, session handling, and roaming support ensures a seamless user experience.
