Security

DNS and TLS form one operational chain of trust even though they solve different problems. DNS answers where a service is located. TLS confirms which server the client reached and whether the connection is protected. A mistake in either layer can invalidate an otherwise correct setup.

HTTP security headers let a server tell the browser how scripts may be loaded, whether a page may be embedded, which device capabilities may be used, how much referrer information should be sent, how MIME types must be interpreted and whether the site may ever be reached over plain HTTP. A well-designed policy reduces the impact of several classes of attacks, including cross-site scripting, clickjacking, MIME confusion, XS-Leaks and unsafe cross-origin embedding.

Most incidents are not sophisticated attacks. They are old problems, outdated software, reused passwords, exposed admin panels, that never got addressed. These are the fundamentals that prevent the majority of trouble.