The classification of IOT use cases can descend from the machine types which are communicating. Therefore IOT use cases can be grouped under Critical or Massive Machine Type Communication (MTC) umbrella.
At high level various V2X (Vehicle to X) centric use cases can fall under Massive Machine type (MMT) use-case group which would need global connectivity. I think Denis has already thrown light on that.
On the other hand use cases like Air traffic control, Smart Grids, Smart multi node factories, public safety and E-health would fall under Critical Machine type (CMT) group. This would also need global connectivity.
Irrespective of the above Security use cases or challenges would vary depending on whether it is a MMT IOT or CMT IOT. The service revenue models and the associated use cases would also differ accordingly.
You may elucidate further and would be happy to help.Regards