# Domain Name System (DNS) The Domain Name System (DNS) is a hierarchical and distributed naming system that translates human-readable domain names (like example.com) into numerical IP addresses that computers use to identify each other on the network. DNS was invented by Paul Mockapetris in 1983, who designed and implemented the system while at USC's Information Sciences Institute, working alongside [[Jon Postel]]. Mockapetris published the original DNS specifications in RFC 882 and RFC 883, later updated by RFC 1034 and RFC 1035, which remain the foundation of DNS today. Before DNS, the ARPANET relied on a single HOSTS.TXT file maintained by the Stanford Research Institute, which became unmanageable as the network grew. DNS operates through a distributed database system organized in a tree-like hierarchy, with the root zone at the top managed by the [[Internet Assigned Numbers Authority (IANA)]]. The system uses a client-server model where DNS resolvers query authoritative name servers to resolve domain names. Key components include root servers (13 logical root server identities, labeled A through M), top-level domains (TLDs like .com, .org, .net), and recursive resolvers that cache responses to improve performance. DNS has evolved to include security extensions (DNSSEC) and privacy improvements (DNS over HTTPS, DNS over TLS). Companies like [[Cloudflare]] now operate major public DNS resolvers (1.1.1.1) alongside traditional providers. ## Related - [[Internet Assigned Numbers Authority (IANA)]] - [[Internet Engineering Task Force (IETF)]] - [[Cloudflare]] - [[Jon Postel]] - [[TCP IP]] - [[ARPANET]] - [[Domain Name System (DNS)]] ## References - https://en.wikipedia.org/wiki/Domain_Name_System - https://www.ietf.org/rfc/rfc1035.txt - https://www.cloudflare.com/learning/dns/what-is-dns/