Functional Testing v Principles testing, Verification and Validation

[PJW]

Broadly.
Certainly uk Principles testing does fit: "undertake testing against the fundamental principles and attempt to “break” the logic".
My interpretation of the "verify that a signalling interlocking is operating in
accordance with design" is more meaning a "systems engineering" approach of having formally defined requirements and traceability that the system delivers these- often uses automated testing to demonstrate that the specified rules are achieved. This I think s more common in places such as France and Germany.

I was asked privately to explain the difference between Principles Testing and Functional testing. The question was asked in the context of Australia.

Hi PJW,
In Mod3 2012 Q2 the question is
Prior to commissioning, some railways verify that a signalling interlocking is operating in
accordance with design. Other railways undertake testing against the fundamental principles
and attempt to “break” the logic. Discuss the advantages and disadvantages of each approach
and the reliance of each approach on control tables and the design process.

Is it true to say what you have described above that functional testing is testing to "verify that a signalling interlocking is operating in accordance with design" ( in this case control table design) and principals testing is "Testing against the fundamental principles and attempt to 'break' the logic"?