4g and 5g network architecture

Let's explore the technical details of the network architectures for 4G (LTE) and 5G (NR - New Radio) mobile communication technologies:

4G (LTE) Network Architecture:

1. eNodeB (Evolved NodeB):
   • In 4G LTE, the primary base station is called the eNodeB. It manages the radio interface, including user equipment (UE) connections, scheduling, and handovers.
2. EPC (Evolved Packet Core):
   • The Evolved Packet Core is the core network architecture for LTE. It consists of several key elements:
     • MME (Mobility Management Entity): Handles mobility and signaling, including tracking, paging, and authentication.
     • SGW (Serving Gateway): Manages user data sessions, packet routing, and forwarding within the LTE network.
     • PGW (Packet Data Network Gateway): Connects the LTE network to external packet data networks, such as the internet.
3. HSS (Home Subscriber Server):
   • The HSS is responsible for subscriber information and authentication in LTE networks.
4. PCRF (Policy and Charging Rules Function):
   • The PCRF determines and enforces policies related to quality of service (QoS) and charging for data services.
5. IMS (IP Multimedia Subsystem):
   • IMS provides multimedia services, including voice and video over IP (VoIP and ViLTE).
6. Interfaces:
   • The key interfaces in the LTE network include S1 (between eNodeB and EPC), S5/S8 (between SGW and PGW), and S11 (between MME and SGW).

5G Network Architecture:

1. gNodeB (Next-Generation NodeB):
   • The gNodeB is the 5G equivalent of the eNodeB in LTE. It handles the radio interface, providing connectivity to user equipment.
2. NGC (Next-Generation Core):
   • The 5G core network, also known as the NGC, is designed to be more flexible and distributed. It includes several key components:
     • AMF (Access and Mobility Management Function): Manages access and mobility, handling functions like registration and handovers.
     • SMF (Session Management Function): Manages user sessions and is responsible for establishing, modifying, and terminating sessions.
     • UPF (User Plane Function): Handles user data packets, routing them between the user equipment and the external data networks.
3. AUSF (Authentication Server Function):
   • The AUSF is responsible for authentication and key generation in 5G networks.
4. UDM (Unified Data Management):
   • The UDM manages user data and subscription information in 5G networks.
5. UDR (Unified Data Repository):
   • The UDR stores structured data such as policy and charging rules.
6. NEF (Network Exposure Function):
   • The NEF enables exposure of network capabilities, allowing third-party applications to interact with the 5G network.
7. AF (Application Function):
   • The AF is responsible for applying policies based on application requirements.
8. Interfaces:
   • Key interfaces in the 5G network include N1 (between gNodeB and AMF), N2 (between gNodeB and UPF), N3 (between gNodeB and SMF), and N4 (between SMF and UPF).

Key Differences:

1. Network Slicing:
   • 5G introduces the concept of network slicing, allowing the creation of virtual networks with specific characteristics for diverse use cases. Each slice is a logically isolated network tailored to the requirements of a particular application or service.
2. Edge Computing:
   • 5G promotes edge computing, where computing resources are placed closer to the network edge. This reduces latency and improves the overall user experience.
3. Service-Based Architecture:
   • 5G adopts a service-based architecture, allowing for more modular and flexible deployment of network functions. This enhances scalability and facilitates the introduction of new services.
4. Control and User Plane Separation (CUPS):
   • 5G introduces Control and User Plane Separation, allowing the independent scaling of control plane and user plane functions for improved resource utilization.
5. Flexibility and Orchestration:
   • 5G networks are designed to be more flexible and adaptable, with increased automation and orchestration capabilities. This is crucial for efficiently managing diverse services and applications.

In summary, the 5G network architecture is designed to be more flexible, scalable, and capable of supporting a wide range of use cases, including enhanced mobile broadband, massive machine-type communication, and ultra-reliable low-latency communication. The transition from 4G to 5G involves a significant transformation in network architecture to meet the demands of evolving communication technologies and applications.