Signaling Screening

Signalling screening is the process of validating each incoming signalling message against policy: is the operation allowed across interconnect, is the originating Global Title or realm legitimate, is the addressed subscriber actually expected to be served by this peer, and does the sequence make sense for the subscriber's known state. It is the day-to-day function of a signalling firewall and is codified in the category model defined by GSMA FS.11 (SS7) and FS.19 (Diameter).

Categories: SignalingRoaming and InterconnectIdentity and Subscriber

Signaling Screening in context

Signaling protocols carry the control-plane messages that set up calls, register subscribers 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 as top-tier telecom risk.

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 Signaling Screening in the wider telecom-security picture, review SS7, Behavioral Signaling Detection, FS.11, TCAP Abuse, Roaming and SS7 Message Categories: each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

Related topic hubs

  • SS7 Firewall GSMA FS.11 category 1/2/3 SS7 message screening at the STP edge.
  • Signaling Firewall Unified SS7/Diameter/GTP/SMS signaling firewall framework.
  • Diameter Firewall GSMA FS.19 screening at the Diameter Edge Agent on S6a/S9/S13.
  • Roaming Security IPX/GRX interconnect risk, home-routed vs local-breakout, SEPP.

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