Transcript domain name system

DOMAIN NAME SYSTEM
By
Gazain Naeem
Domain Name System is the hierarchical
computer system which is connected to the
internet. It works like a telephone directory
system for the internet network where you
know the name of a particular person and you
want to find out the number of that person.
www.google.co.uk
In this example:
• www is the service provider.
• Google is the hostname.
• .co is the domain space.
• .uk is the country code.
Three important components
• Domain name space: It is an aspect of DNS which consists of a tree of
domain names. It starts off from the root, than TLDs (Top-Level Domain)
and than Secondary-Level Domain. Each leaf or node might have zero or
more RRs (Resource Records) which has information related to the
Domain name.
• Name resolution: It is the method of translating website name to IP
address. When TCP/IP uses DNS as a method of resolution, the host that is
trying to get resolution is called a resolver. The resolver sends a message
to its DNS server asking for help.
• Name server: Name server or DNS server is a server that implements a
name-service protocol. It can be on the same network or it can be at an
ISP.
FUCTION
First the client (end user) enters a URL into the
web explorer. Then the client sends a request to
a DNS server on a local ISP to receive the IP
address. If the IP is not on the local ISP cached
server, it searches for another DNS server
(mainly in TLDs eg .com) and when it gets the IP
it wants, the ISP receives the IP, temporarily
saves the IP on its own server and sends it to the
client. The client receives it and then has access
to the desired website.
LEGISLATION IN THE UK
The operation of the Domain name system does
not affect any legislation in the UK as it is a chain
of international companies that runs the DNS
severs all over the world and they decide DNS
matters. The British law can be a part of it or can
be influenced by it, but it still has a very minor
affect on it.
LIMITATIONS
We have an unlimited number of IP addresses hypothetically.
Internet Protocol version 4 (IPv4) is the first internet protocol
to be broadly used all over the world and the fourth revision
in the advancement of the Internet protocol. Due to the
enormous growth of the internet, IPv4 is no longer viable.
Internet Protocol version 6 (IPv6) will soon replace IPv4 as the
internet standard. IPv6 sometimes is referred to as Internet
Protocol, Next Generation (IPng). IPv4 has some limits, like 4
billion because there are 32 bits in every address but IPv6
enables to give every individual on the planet, which gives the
6 billion indiviuals we have now on the planet, 10 billion IP
addresses because it uses 128-bit addresses.
BIBLIOGRAPHY
• Blank, A.G. (2002). TCP/IP JumpStart. USA: SYBEX.
• Hewitt, S. (2003). Domain Name System. Available:
http://en.wikipedia.org/wiki/Domain_Name_System.
Last accessed 03/12/2011.
• Domain Name System (DNS) How It Works, 2009,
online video, accessed 02 December 2011,
<http://www.youtube.com/watch?v=eX7Yt_fxAfU>.
• Domain Name Services, 2008, online video, accessed
03 December 2011,
http://www.youtube.com/watch?v=9RhOSxZ1WJk
• Odom, W. (2004). Computer Networking first-step.
USA: Cisco Press.