3gpp core network

The 3GPP (3rd Generation Partnership Project) core network is a crucial part of the mobile telecommunications system, especially in 3G, 4G (LTE), and 5G networks. It ensures the end-to-end communication between user equipment (UE) or devices and external networks such as the internet or other operator networks. Let's delve into its technical aspects:

3GPP Core Network Components:

1. Mobility Management Entity (MME):
   • Acts as the control plane entity for the LTE access network.
   • Handles the signaling for setting up, maintaining, and releasing connections for mobile devices.
   • Responsible for functions such as UE authentication, security, and mobility management including tracking area updates and handovers.
2. System Architecture Evolution Gateway (S-GW):
   • Serves as the user plane endpoint.
   • It routes data packets to and from the User Equipment (UE) within the LTE network.
   • Performs functions like packet routing, forwarding, and mobility anchoring.
3. PDN Gateway (P-GW):
   • Acts as the interface between the 3GPP network and external packet data networks like the internet.
   • Manages IP address allocation for the UE.
   • Responsible for policy enforcement, charging, and other functions related to data services.
4. Home Subscriber Server (HSS):
   • Central database that contains subscriber information.
   • Stores subscription-related information, mobility and session management parameters, and security credentials for each user.
5. Policy and Charging Rules Function (PCRF):
   • Determines policy rules for services and charging.
   • Responsible for policy control decisions and for communicating these decisions to the P-GW.

Key Technical Aspects:

1. Signaling Protocols:
   • The core network uses protocols like Diameter (an evolution of RADIUS) for signaling between network elements such as MME, HSS, and P-GW.
   • S1-MME and S11 are interfaces used for signaling between MME-S-GW and MME-P-GW, respectively.
2. User Plane Protocols:
   • GTP (GPRS Tunneling Protocol) is used for creating tunnels between the S-GW and P-GW for user data transfer in LTE networks.
3. Security:
   • Authentication and key agreement (AKA) mechanisms are used to ensure the security of communication.
   • Encryption and integrity protection mechanisms are employed to safeguard user data.
4. Mobility Management:
   • The core network manages mobility by tracking the location of UEs, performing handovers between base stations, and ensuring uninterrupted services as UEs move between cells and areas.
5. Quality of Service (QoS):
   • The core network uses mechanisms to ensure QoS for different types of services, such as voice, video, and data, by applying policies at the P-GW based on the PCRF decisions.
6. Interworking with External Networks:
   • The P-GW facilitates communication between the 3GPP network and external networks by translating protocols and managing data sessions.

Evolution and Enhancements:

• The 3GPP core network has evolved over time with the introduction of new technologies, such as VoLTE (Voice over LTE), IoT (Internet of Things) support, and enhancements to support higher data rates, lower latency, and improved efficiency in 4G and 5G networks.

3GPP core network comprises various components working together to provide mobility management, data routing, security, and other essential functions required for delivering mobile services to users efficiently.