Domain Name Server / Services is one of the main concerns on the Internet. The popularity brought to Internet through Domain Name Servers / Services.
Domain Name Servers – It refers to a protocol
Domain Name Services – It is the Service provided
DNS related to ARPANET and thereafter Alphabetic Names of Host Websites in order to eliminate the difficulties of memorizing Domains.
Initially, for websites connected to ARPANET a file named HOSTS.TXT defined all numeric addresses that made use. This caused a lot of problems in the setup of the hostnames.
In the year 1973, Host Names Online introduce which was rigorously worked upon leading to RFC 625 revolution in the year 1974, and came up with Stanford Network Information Center which was a centralized location for the Information of Host.
However, this reduced the efficiency time to keep a complete record of the Information of the Host.
In 1983, new plans in RFC 881,882 and 883 were named ‘The Domain Names Plan and Schedule’Domain Names — Concepts And Facilities,’ and ‘ Domain Names — Implementation And Specification.’
Functions of DNS –
> DNS differentiates IP addresses to hostnames
> This was the aim of human users.
> Types of Servers –
> Root Name Server – Each Main Domain has RNS, they are relatively static and easily reachable.
> Authoritative Name Servers – RNS directs information to ANS. The information on the Domain stored in Zone Files.
> Resolving Name Server – They help in looking up Data or Storing the Data stored in Cache.
> If a website, for e.g. – http://www.bodhost.com/, type it > queries sent through Resolving NS and located its IP address.
> It checks Cache initially, if it does not exists then it goes up to check with .org RNS in order to locate ANS, once located, it connects thereafter.
> Once resolving Name Server informed by ANS, it responds back with the appropriate IP address and simultaneously in connection to the webserver and locates thereafter, if not an error reported.