Defense in Depth, Medieval Style

The article describes the medieval defensive system of Constantinople, comprising four layers: a ditch, a low breastwork, an outer wall, and a main wall. This system is a prime example of 'defense in depth' and its design made it nearly unscalable. The layout and design of the walls and moat made it difficult for enemies to breach the defenses. This concept is still relevant in modern IT security, where multiple layers of defense are used to protect against threats. Engineers can learn from this historical example and apply similar principles to their own security systems.