DNS, Network Protocols and Security

This course introduces the foundational concepts of the Domain Name System (DNS) protocol, how it functions in practice, and the security-relevant behaviors that every practitioner working in a security role should understand. DNS is a deceptively complex protocol, and while its core concept is simple, real depth emerges once caching, resolution chains, and adversarial abuse are considered. This material walks through the core functionality of the protocol and highlights concepts that every security practitioner should be aware of.

Domain Name System (DNS) is a complicated protocol with quite a bit of depth. Even though the fundamental concept is simple, do not be surprised to find yourself still learning new things about DNS behavior deep into a cybersecurity career.

At its core, DNS solves one problem: when a computer browses to a web address such as pluralsight.com, the operating system needs to convert that human-readable domain name into an IP address that can actually be routed on the network. DNS is the protocol that accomplishes this translation.