Sign in Subscribe

N3IWF Non-3GPP Interworking Function

Last updated on 

Introduction

The Non-3GPP Interworking Function (N3IWF) is a component of the 5G Core (5GC) network architecture that provides a seamless interconnection between 5G Core networks and non-3GPP networks. Non-3GPP networks include networks such as Wi-Fi, Ethernet, DSL, and cable networks. N3IWF provides the necessary interworking functions to allow communication between 5G Core networks and non-3GPP networks. This article will provide an in-depth explanation of N3IWF and its role in 5G network architecture.

N3IWF Functions

The N3IWF has several primary functions in the 5G network architecture, including:

  1. Interworking with non-3GPP networks: The N3IWF provides interworking functions between 5G Core networks and non-3GPP networks. It enables seamless communication between the two types of networks by converting the signaling and user data between the two networks.
  2. Authentication and security: The N3IWF is responsible for providing authentication and security functions for the non-3GPP network users. It ensures that only authorized users are allowed to access the network and that all data transmitted is secure.
  3. Session management: The N3IWF is responsible for managing the session between the non-3GPP network and the 5G Core network. It maintains the session state and ensures that the session is active throughout the communication.
  4. Charging: The N3IWF is responsible for charging the non-3GPP network users for the services they use. It keeps track of the usage of the network and applies the appropriate charges based on the user's usage.

N3IWF Architecture

The N3IWF is an integral part of the 5G network architecture and is located in the Access and Mobility Management Function (AMF) domain. The N3IWF can be implemented in two different ways, as a standalone entity or as an integrated entity within the User Plane Function (UPF). The standalone N3IWF is connected to the 5G Core network via the N3 interface and to the non-3GPP network via the non-3GPP access network interface.

The integrated N3IWF is located within the UPF and is connected to the 5G Core network via the N4 interface and to the non-3GPP network via the non-3GPP access network interface. In this architecture, the UPF acts as a single point of connection between the 5G Core network and the non-3GPP network.

N3IWF Protocol Stack

The N3IWF uses several protocols to ensure seamless interworking between the 5G Core network and non-3GPP networks. These protocols include:

  1. N3IWF Control Plane Protocol (N3IWF-CP): This protocol is used for communication between the N3IWF and the AMF. It is responsible for session management and authentication of non-3GPP network users.
  2. N3IWF User Plane Protocol (N3IWF-UP): This protocol is used for the transmission of user data between the non-3GPP network and the 5G Core network. It is responsible for converting the user data between the two networks and ensuring its integrity and security.
  3. Non-3GPP Access Network Protocol (ANP): This protocol is used for communication between the N3IWF and the non-3GPP access network. It is responsible for signaling and user data transmission between the two networks.
  4. 5G Core Network Protocol (N4): This protocol is used for communication between the integrated N3IWF and the 5G Core network. It is responsible for session management and user data transmission between the two networks.

N3IWF Interfaces

The N3IWF has several interfaces that enable communication between the different components of the network. These interfaces include:

  1. N3 interface: This interface is used to connect the standalone N3IWF to the 5G Core network. It is responsible for communication between the N3IWF and the AMF.
  2. Non-3GPP access network interface: This interface is used to connect the N3IWF to the non-3GPP access network. It is responsible for signaling and user data transmission between the two networks.
  3. N4 interface: This interface is used to connect the integrated N3IWF to the 5G Core network. It is responsible for communication between the N3IWF and the UPF.

Benefits of N3IWF

The N3IWF provides several benefits to the 5G network architecture, including:

  1. Seamless interworking between 5G Core networks and non-3GPP networks: The N3IWF enables seamless communication between the two types of networks, providing a consistent user experience regardless of the network used.
  2. Enhanced security: The N3IWF provides authentication and security functions for non-3GPP network users, ensuring that only authorized users are allowed to access the network and that all data transmitted is secure.
  3. Improved session management: The N3IWF is responsible for managing the session between the non-3GPP network and the 5G Core network, ensuring that the session is active throughout the communication.
  4. Efficient charging: The N3IWF is responsible for charging the non-3GPP network users for the services they use, ensuring that the charges are applied appropriately based on the user's usage.

Conclusion

The Non-3GPP Interworking Function (N3IWF) is an essential component of the 5G network architecture that provides a seamless interconnection between 5G Core networks and non-3GPP networks. It enables seamless communication between the two types of networks by converting the signaling and user data between the two networks. The N3IWF provides several benefits to the 5G network architecture, including seamless interworking, enhanced security, improved session management, and efficient charging.