5G-GUTI (5G Globally Unique Temporary Identifier)

In telecom networks, the 5G-GUTI is a temporary subscriber identifier assigned by the AMF that is used in place of the SUPI on the radio interface to limit identity exposure. Frequent 5G-GUTI reallocation reduces the ability of attackers to track a subscriber over time.

Categories: Radio Access NetworkCore NetworkIdentity and Subscriber

5G-GUTI 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 5G-GUTI in the wider telecom-security picture, review TMSI, UPF, MNO, Confidentiality, Encryption and VRAN: each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

Related topic hubs

  • 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
  • 5G NEF Security Network Exposure Function security in the 5G core.
  • NAS Security Non-Access Stratum security, integrity and ciphering algorithms.
  • 5G Penetration Testing Pentesting the 5G core, SBA, SEPP, and gNB interfaces.

More from the TelcoSec Glossary

Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.