DMZ Security Architecture Best Practices

Quick Answer

Placing the web server in the DMZ while keeping the file server on the internal network, and restricting the path between them to only HTTP/HTTPS, provides the strongest security because it applies two complementary principles at once: least privilege and defense in depth. The DMZ exists specifically to host systems that must be reachable from the internet, isolating them in a buffer zone so that a compromise of the internet-facing service doesn't automatically expose the rest of the internal network. Keeping the file server internal, rather than also placing it in the DMZ, removes it from direct external exposure entirely; the only way to reach it is through the narrow, controlled channel of HTTP/HTTPS traffic originating from the web server, typically enforced by a stateful firewall or application-layer gateway. This matters because if the web server is ever compromised, the attacker inherits only the limited HTTP/HTTPS access the firewall permits, not full network-level reach into the internal file server, which sharply reduces the blast radius and makes lateral movement much harder. A weaker design, such as placing both servers in the DMZ or allowing broad connectivity between them, would let a single compromised system become a launchpad into everything else. When a question asks you to compare DMZ architectures, favor the option that minimizes both what's exposed externally and what a compromised DMZ host can reach internally.