Interconnect Security Model

The interconnect security model defines how operators authenticate each other, encrypt their exchanges, and authorise specific signalling operations between networks. Modern best practice combines transport-layer protection (IPsec or TLS), application-layer authentication and integrity (SEPP/PRINS in 5G), category-based message filtering (GSMA FS.11 for SS7, FS.19 for Diameter), and behaviour-based monitoring. The goal is to move the interconnect from implicit trust to verifiable, least-privilege exchanges between every pair of partners.

Categories: Radio Access NetworkSignalingRoaming and Interconnect

Interconnect Security Model in context

The radio access network is the layer where mobile devices attach to the operator's infrastructure. Attacks in this layer include IMSI catching, rogue base stations, downgrade attacks and jamming, and defenses hinge on mutual authentication, integrity-protected signaling and Open RAN supply-chain hygiene.

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.

To place Interconnect Security Model in the wider telecom-security picture, review IBCF, Inter-PLMN Security, PLMN, Roaming Security Architecture, Firewall and GRX.

Related terms

Related topic hubs

  • Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.
  • Signaling Firewall Unified SS7/Diameter/GTP/SMS signaling firewall framework.
  • Roaming Security IPX/GRX interconnect risk, home-routed vs local-breakout, SEPP.
  • 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.

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.