NRF (Network Repository Function)

The Network Repository Function is the 5G core service registry: every Network Function registers its profile and capabilities with the NRF, and consumers query the NRF to discover producers. The NRF authenticates clients via OAuth2 access tokens and mutual TLS, and unauthorised access could let an attacker enumerate the entire 5G core or impersonate a service. Hardening the NRF and its NFprofile data is therefore central to Service-Based Architecture security.

Categories: Radio Access NetworkCore NetworkSignaling

NRF 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 NRF 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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