Plain-language definition
The signaling network that mobile networks use to set up calls, route SMS and locate subscribers.
Technical definition
SS7 is a layered protocol suite (MTP, SCCP, TCAP, MAP, CAP, ISUP) originally over TDM, now commonly over IP via SIGTRAN.
Why it matters
SMS routing, HLR queries and roaming all depend on SS7; its trust model predates modern threats, so SMS-layer screening is required.
Last reviewed 2026-09-12 by the Guardivia QoS Engineering Team. Product facts on this page describe current capabilities; items marked “where supported”, “optional”, “integration” or “consultancy” are confirmed per deployment.