N2 Handover (N2-based Handover)

N2 handover is the 5G handover procedure (3GPP TS 23.502) executed via the AMF over the N2 interface when the Xn interface is unavailable between source and target gNBs, or for inter-AMF mobility. The AMF orchestrates the target-side resource setup, path switch on the UPF, and NAS security context transfer. Slower than Xn but mandatory for AMF changes.

Categories: Radio Access NetworkCore NetworkSignaling

N2 Handover in context

The radio access network is where mobile devices attach to the operator's infrastructure. Attacks in this layer include IMSI catching, rogue base stations and downgrade attacks; defenses rest on mutual authentication, integrity-protected signaling and Open RAN supply-chain hygiene.

The mobile core carries subscriber sessions, mobility and policy. In 4G it is the EPC (MME, HSS, S/PGW); in 5G it is the Service-Based Architecture with AMF, SMF, UPF, AUSF, UDM and the NRF.

To place N2 Handover in the wider telecom-security picture, review 5G SA, AMF, Base Station (BS), Capacity Planning, CAPEX and CSCF — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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