FS.40 (5G Security Guide)

In telecom networks, GSMA FS.40 is the high-level operator security guide for 5G, covering the SBA, network slicing, virtualization, edge computing, and interconnect, and pointing to detailed documents such as FS.36 for inter-PLMN security.

Categories: Core NetworkRoaming and InterconnectProtocols and Standards

FS.40 in context

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.

Roaming and interconnect are where two operators 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.

To place FS.40 in the wider telecom-security picture, review PRD, AES, AUSF, Conformance Testing, Cryptography and EIR — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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