DNS Domain Name System:
DNS is a system on the
Internet that allows a clear name for the address of each computer connected to
the net and is used universally. Therefore, both the user and the application
can use DNS name instead of IPnet's numeric address. This has many advantages
and the fact that the name is a much easier and simpler method to use than a
number. This allows the organization to keep the names of machines, services
and e-mail addresses etc. independent of the specific number addresses that the
working systems may be using at the time. Such as when changing the topology of
the net or when changing the provider to access the Internet.
Technically, DNS is a
database distributed over the Internet as a hierarchy. There are innumerable
servers that find this out by interacting with each other and by translating
the names to the respective IP addresses by the customer applications that
contact them. Connection can be established. Each part of the database has a
replica on at least two servers and it determines the redundancy factor. The
biggest reason behind the growth and use of DNS on the Internet was the amazing
increase in the number of connected machines on the network. Initially, the
link between the number and the IP address was created by a ready-made list in
the host file (Host.txt) which was updated every time a new system was added
and needed to be on every computer connected to the Internet.
Larger installations have
innumerable different groups of names to organize. This includes users and
their passwords, names and network addresses for computers and accounts.
Keeping this data updated on all computers has become very complicated. Hence
the database is now kept on only a few systems.
For Internet users to
access a web site, their computer needs to know the address of the web server
hosting that site. Computers on the Internet recognize each other by number
rather than letters or words. Each web site on the Internet has a domain name
and numeric address. Which is called (IP address) Internet Protocol address.
(Example, 205.139.94.60). Though this number is simple for computer but
difficult for internet users to remember. Hence the need for a domain name.
World Wide Web:
The World Wide Web (also
known as the Web or www or W3) is an area of the Internet that has achieved
amazing achievements over the years. Many people consider the web to be the
internet, whereas the web is only a part of the internet but a main part is
made up of web sites, sites where someone has kept files and which are
connected by people connected to the internet. Can be accessed. All files are
of different types, text, graphic, video or sound etc. and are located on
computers around the world. It has a wealth of information on many topics.
These files can be
obtained by IP address and http protocol (Hypertext Transfer Protocol). The Web
works on the Client-Server Model. You use a client program that sends your
request to the server for information. The server receives the information and
sends it to the client. The browser software used to access the web is called a
browser. Netscape Navigator and Microsoft Internet Explorer with the help of
well-known browsers, we can view graphic files on the web. There are also some
text-only-browsers such as Lynx.
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