What does "security through systematics" mean, and how does it contrast with "security by obscurity"?

Question

Accepted Answer

Security should come from sound, systematic, well-understood design — not from hiding how the system works (security by obscurity).
Security by obscurity relies on keeping the design or mechanism secret as the main protection ("they can't attack what they don't understand"). It's fragile: once the secret leaks — and it eventually does — the protection collapses entirely.
Security through systematics instead builds protection into the architecture and methodology: defenses that hold up even if the attacker knows exactly how the system works. This aligns with Kerckhoffs's principle in cryptography — a system should stay secure even if everything about it except the key is public.
Tip: Obscurity can be a thin extra layer, but never the foundation. "We're safe because no one knows our setup" is a red flag, not a strategy.
Go deeper:

Kerckhoffs's principle (Wikipedia) — the cryptographic basis for "secure even if the design is public," with a dedicated critique of security through obscurity.