5G-AKA (5G Authentication and Key Agreement)

The primary authentication protocol used in 5G networks to mutually authenticate the subscriber and the network. 5G-AKA enhances the security of its predecessors (EPS-AKA, UMTS-AKA) by providing stronger key derivation, home network verification of authentication results, and protection against certain IMSI-catching attacks through the use of SUPI/SUCI concealment mechanisms.

Categories: Roaming and InterconnectIdentity and SubscriberSecurity Controls

5G-AKA in context

Roaming and interconnect are where two operators, often with an IPX or GRX carrier in between, exchange signaling and user-plane traffic. Trust boundaries here are the primary attack surface for location tracking, SMS interception and fraud, which is why GSMA now mandates SEPP with PRINS on 5G interconnect.

Subscriber identifiers (IMSI, SUPI, MSISDN, IMEI) are the anchor for authentication, charging, lawful interception and fraud analytics. Any protocol or interface that leaks a permanent identifier is treated as a serious privacy defect, which is why 5G introduced SUCI concealment on the air interface.

To place 5G-AKA in the wider telecom-security picture, review AAA, AKA, Diameter Interconnect Security, IMSI, iSIM and Roaming.

Related terms

Related topic hubs

  • 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
  • Roaming Security IPX/GRX interconnect risk, home-routed vs local-breakout, SEPP.
  • Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.
  • SMS Firewall SMS spam, phishing, A2P bypass and MAP-layer SMS filtering.

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