FASG (GSMA Fraud and Security Group)

Also known as: GSMA FASG, Fraud and Security Group

In telecom networks, the GSMA Fraud and Security Group (FASG) is the industry body that produces FS-series technical documents covering interconnect security (SS7, Diameter, GTP, 5G), fraud, and operational best practices. FASG outputs feed the T-ISAC, NESAS, and operator security baselines, and coordinate fraud and security initiatives across mobile operators worldwide.

Categories: SignalingRoaming and InterconnectFraud

FASG in context

Signaling protocols carry the control-plane instructions that set up calls, register subscribers, hand over sessions and route SMS. SS7, Diameter, GTP-C and SIP are the four dominant families, and interconnect exposure of any of them is treated by GSMA FS.11 / FS.19 / FS.20 as a top-tier telecom risk.

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.

To place FASG in the wider telecom-security picture, review Firewall, FS.07, FS.11, FS.36, FS.21 and GSMA Open Gateway.

Related terms

Related topic hubs

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.