DNS, or the Domain Name System, is a naming database that translates human- readable domain names into machine-readable IP addresses
. It acts as a phonebook for the internet, connecting web browsers with websites
. The process of DNS resolution involves several steps:
- The user enters a web address or domain name into a browser.
- The browser sends a message, called a recursive DNS query, to the network to find out which IP or network address the domain corresponds to.
- The query goes to a recursive DNS server, which is usually managed by the internet service provider (ISP).
- The recursive resolver forwards the query to a root name server, which responds with the names of the top-level domain (TLD) name servers for the domain.
- The recursive resolver forwards the query to one of the TLD name servers for the domain.
- The TLD name server responds with the names of the authoritative name servers for the domain.
- The recursive resolver chooses an authoritative name server and forwards the query to it.
- The authoritative name server responds with the IP address associated with the domain name.
- The recursive resolver stores the IP address in its cache, so that future queries for the same domain name can be resolved more quickly.
DNS servers are essential for web browsing and most other internet activities, as they translate what a user types into a browser into something the machine can use to find a webpage
. There are four types of DNS servers involved in the resolution process: DNS resolver, root nameserver, TLD nameserver, and authoritative nameserver
