Interworking Security

Interworking security is increasingly critical as networks become more interconnected. Collaboration between mobile network partners helps secure communication channels and prevent breaches. The GSMA offers key documentation to assist operators in mitigating risks associated with protocols such as SS7, DIAMETER, SIGTRAN, and IPX networks. These resources cover types of SMS and signalling fraud, SIM box bypass methods, and how to secure communication protocols.

For mobile operators, interworking security is essential for maintaining a seamless and secure global communication system. By applying best practices from these documents, operators can establish effective firewalls, monitor traffic, and secure signalling layers. This page also provides resources on global title leasing and key management for 5G and LTE interconnections. Access to this knowledge helps operators detect vulnerabilities early and work closely with partners to maintain strong network security.

Document	Description	Access
Use of SIM Boxes to Bypass Interconnect Communications (FS.01)	This document defines various types of SIM box bypass and their impact on traffic flows. It also outlines the mechanisms used to detect SIM boxes.	Members only
SMS Fraud (FF.09)	This document introduces different types of SMS. It illustrates how normal SMS traffic flows through the network and explains how fraud scenarios arise.	Members only
A2P SMS Bypass and Fraud – Methods, Detection and Mitigation (FS.12)	This document describes the risks associated with application-to-person SMS bypass, SMS artificial inflation of traffic and unauthorised HLR lookups. It also provides mitigation recommendations.	Members only
SMS Firewall Best Practices and Policies (SG.22)	This guide offers high-level guidelines to help operators implement and manage SMS firewall policies. It also suggests corrective actions when necessary.	Members only
Binary SMS Filtering Guidelines (FS.42)	This document describes exploitations of binary SMS. It outlines where controls can be applied across network control points for each binary SMS type.	Members only
SS7 and SIGTRAN Network Security (FS.07)	This document analyses SS7 and SIGTRAN stack layer security. It identifies threats, describes attack methods, and proposes best practice countermeasures.	Members only
SS7 Interconnect Security Monitoring and Firewall Guidelines (FS.11)	This guide helps mobile operators monitor SS7 traffic and set firewall rules. It also supports establishing data-sharing capabilities to improve security.	Members only
Global Title Leasing Code of Conduct (FS.52)	This document addresses the leasing of global titles (GTs) within SS7 networks. It explains GT usage motivations and introduces a code of conduct to prevent abuse.	Public
Diameter Interconnect Security (FS.19)	This guide outlines potential diameter-based attacks on mobile networks and customers. It also offers countermeasures to enhance LTE and 5G interconnection security.	Members only
GPRS Tunneling Protocol (GTP) Security (FS.20)	This document describes attacks on the mobile core network performed through the general packet radio service (GPRS) exchange (GRX), the internet protocol exchange (IPX) network or the internet. It also addresses mitigation strategies and countermeasures.	Members only
GTP-U (FS.37)	This document provides recommendations for mobile network operators to detect and prevent attacks using GPRS tunnelling protocol user (GTP-U) plane data.	Members only
5G Interconnect Security (FS.36)	This guide outlines potential 5G interconnect attacks on mobile networks and customers. It also provides countermeasures to address threats and risks related to 5G interconnection security.	Members only
Interconnect Signalling Security Recommendations (FS.21)	This document introduces interconnect signalling security with a risk-based approach. It also includes technical recommendations on packet categorisation, protocol correlation, firewall implementation.	Members only
Interconnect Testing (FS.26)	This document outlines the security roles and responsibilities of testers and signalling interconnect partners. It is relevant when performing remote interconnect signalling security testing.	Public
Key Management (FS.34)	This document details key management processes, including the exchange of certificates and key materials, between interconnect parties to secure signalling communications.	Public
SIP (FS.38)	This guide outlines potential SIP-based security, privacy, and fraud attacks on fixed, mobile, and converged networks. It also describes countermeasures to mitigate these risks.	Members only
RCS Fraud and Security Assessment (FS.41)	This document provides an overview of the fraud and security risks related to the implementation and deployment of RCS. It also provides guidance on how to mitigate those risks.	Members only
Flash Calls Fraud and Security Assessment (FS.66)	This document describes flash and voice OTP TTS calling fraud and security risks to a range of stakeholders.	Members only

Please note, resources marked ‘Members only’ can only be accessed by GSMA members