The jump from 11 to 12 is crossing the atlantic ocean.

So the answer is min(Rs, Rc).

Layering can be harmful because each layer is only responsible for its own job, so if the presentation layer doesn’t encrypt, no other layers job to do that.

Internet protocol stack is a practical perspective, ISO/OSI reference model is a reference perspective. The missing layers (presentation, session) must be implemented in the application layer if needed.