DNS (Domain Name System) is one among the foremost necessary technologies/services on the web. DNS provides a reputation to variety (IP address) mapping or translation, permitting web users to use, straightforward to recollect names, and not numbers to access resources on a network and the web.
DNS Basics – Understanding Why we want it
All devices (computers etc) that are connected to the web, your own network, or company network are known by AN information processing address; that may be a variety.
On early pc networks an easy document known as a hosts file was created that mapped host names to information processing addresses.
Here is that the host file taken from my computer. It comes with all Windows machines
Host file on Windows computer
The location for the hosts file is often C\windows\system32\drivers\etc
As network sizes enhanced the hosts file approach became impractical thanks to the fact that:
It required to be hold on every pc
The document might take a on time to method thanks to the fact that it had been unstructured.
Updates were tough to manage as all the computers would wish to tend an updated file.
A way to prepare the names- name structure
Protocols, services and strategies for storing, updating, and retrieving information processing addresses for hosts computers. – DNS System
From the angle of a user you’ll be able to think about the DNS system as a structured hosts file.
Domain Name Structure
The hosts file is solely a listing of names and information processing addresses with no structure creating it tough to scale to an outsized variety of machines.
The solution is to position the machines into body areas called domains and organize the domains in a very hierarchy.
This takes the shape of a tree like structure that resembles the filing system structure found on computers. See Understanding the Name Structure
The DNS system consists of the many name servers that along offer the name to information processing address mapping for registered devices (usually servers) on the web.
The main DNS severs (root servers) are in hand and managed by a spread of various organizations and are placed chiefly within the USA.
Other firms together with ISPs have their own DNS servers that are joined to the foundation servers in a very graded fashion providing a distributed system.
Fortunately, you don’t ought to manage a DNS server or produce DNS records to use the web.
However, you would like to possess access to a DNS server.
To access a DNS server, you may want the information processing address of the DNS server.
DNS Name Resolution
To resolve a bunch name to AN information processing address mistreatment DNS you may ought to have s DNS shopper on your machine, and the shopper should understand the information processing address of a DNS server.
The DNS shopper queries its DNS server that then follows through a method to induce AN answer- See DNS lookups explained.
Host Name Resolution
DNS and Host are 2 name resolution strategies however they’re not the sole ones.
A Windows shopper can use DNS, Hosts And different strategies to resolve a bunch name or pc name to an information processing address. See Understanding Host name resolution strategies.
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