VPN-UPLINK - Encyclopedia: DNS (Domain Name System)
The Domain Name System or DNS is a system that stores information about hostnames and domain names in a type of distributed database on networks, such as the Internet. Of the many types of information that can be stored, most importantly it provides a physical location (IP address) for each domain name, and lists the mail exchange servers accepting e-mail for each domain.
The DNS provides a vital service on the Internet as it allows the transmission of technical information in a user-friendly way. While computers and network hardware work with IP addresses to perform tasks such as addressing and routing, humans generally find it easier to work with hostnames and domain names in URLs and e-mail addresses. The DNS therefore mediates between the needs and preferences of humans and of software.
The practical operation of the DNS system consists of three players:
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Domain Name System (DNS)".
- The DNS resolver, a DNS client program which runs on a user's computer and generates DNS requests on behalf of software programs.
- The recursive DNS server, which searches through the DNS in response to queries from resolvers and returns answers to those resolvers.
- The authoritative DNS server which hands out answers to queries from recursors, either in the form of an answer, or in the form of a delegation (i.e. referral to another authoritative DNS server).