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DNS terms

DNS terms cover the Domain Name System. DNS is like a phonebook for the internet. It translates website names into numbers that computers understand.

DNS fallback

DNS fallback is a mechanism where a client or resolver attempts to use an alternative DNS server or resolution method when the primary DNS resolver fails entirely, such as due to a server crash or network failure.

Response rate limiting

Response rate limiting (RRL) is a server-side traffic control mechanism that restricts the number of similar or identical responses a service — most often a DNS server — sends to the same IP address or subnet within a short time window.

DHCID record

A DHCID record is a specialized type of DNS record that binds a DNS name to a unique client identity as seen by the DHCP (Dynamic Host Configuration Protocol) server.

DNAME

DNAME is a type of DNS (Domain Name System) record that allows redirecting domain namespace subtrees to other domains.

HINFO record

An HINFO record is a type of DNS record that describes the hardware and OS characteristics of a specific host.

Authoritative DNS server

An authoritative DNS server is a server that holds the official details about a website's IP address.

Recursive DNS server

A recursive DNS server helps find the IP address of a website.

The importance of DNS terminology

DNS translates easy-to-remember names into the IP addresses computers use. Knowing the vocabulary behind it makes it easier to configure devices, diagnose issues, and keep your browsing more private and secure.

Know what to do

This glossary explains how to troubleshoot DNS-related issues, such as websites not loading or slow browsing speeds, and how to change your DNS settings for better performance or privacy.

Understand how DNS works

Learning how DNS translates domain names into IP addresses and how DNS servers operate will help you understand why you can access a website by name, rather than a long numerical address.

Secure your browsing

Learn about and know how to use encrypted DNS, enable DNSSEC validation, choose trusted resolvers, and set up leak protection to prevent spoofing, avoid DNS leaks, and keep your lookups private.

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