That's one approach, but some operators have SS7 connections to unknown providers. And turning off connections is a great way to discover that a whole host of s

That's one approach, but some operators have SS7 connections to unknown providers. And turning off connections is a great way to discover that a whole host of services (think Twilio etc) suddenly stop working, as they were using some sketchy forgotten-about route into the network. With third party access often "leased" via legitimate-ish providers though, it's hard to really do this without cutting countries or territories loose. Small countries often have operators that give SS7 access, to raise some extra revenue they can't get from their (small and population limited) subscriber-base.