At least over Switzerland actually goes a wave of extreme Caller ID Spoofing because health insurance deadlines, banking services no more needed and M(V)NOs operating in a highly saturated market with shrinking revenues.
As voice signalling over 3G (UMTS) is different to VoLTE Voice over LTE (or LTE Advanced and LTE Advanced Pro based on 3GPP R15 standards) its worth discussing with technical forms/possibilities which are possible to be confronted with.
We actually do not understand how this works that missing numbers are either transmitted correctly or suppressed to confuse the receiver. Who can help to display all possible technical CLIP Caller Line Identification Presentation forms?
A unique form of spoofing we received a few weeks ago. The receiver just took a call and from the start lets say second 0.00 he was heavily charged by a tarif of 175 USD/min. You can calculate divided by 60 you get close to 3 bucks/second. A crime architecture behind signalled the call as the receiver already agreed to a high price service to get called back - which was not the case.
In short Taking a call will destroy your cash immediatelly.
By posting here experiences of different countries will help that collaborative learning would fasten the process of enforcement. See criminals collaborate faster and more openly than LEOs. This cannot be solved but improved by fast collaboration - all can learn. Not how to set up but how it appears in the public.
Please share the phenomenas you face. Thank you.