5G • Core Network

N3IWF

Non-3GPP InterWorking Function

Security gateway enabling untrusted access networks (e.g. public Wi-Fi) to securely connect to the 5G Core.

Technical Explanation

The N3IWF anchors untrusted non-3GPP access. It terminates an IPsec tunnel from the UE (running IKEv2), establishes standard N2 control plane signaling to the AMF, and encapsulates user data into GTP-U over N3 to the UPF. This allows seamless roaming between Wi-Fi and 5G cellular coverage.

Key Functions

  • Terminates secure IPsec / IKEv2 tunnels from UEs over untrusted Wi-Fi
  • Interfaces to AMF via standard N2 and UPF via standard N3 GTP-U
  • Enables seamless handover between Wi-Fi and 5G cellular access
Specifications
3GPP TS 23.501, TS 23.502
Interfaces
N2N3NWu

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