untangling_the_web

DOCID: 4046925
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Understanding Domain Name and
Whois lookup Tools
Domain names are nothing more than aliases for IP addresses; they are a-convenience
for human beings, who have more trouble remembering long numbers than
letters, words, and names. But computers love numbers, so every time you enter a
uri (an address that contains the protocol, host, domain, directory, and file
information), the computers that really are the Internet translate that name into its
corresponding IP address. How do the computers know what domain name matches
which IP number? DNS: the domain name system (or service). DNS is the Internet
service that translates domain names, such as www.amazon.com. into IP
addresses.
DNS is a huge distributed database residing on a network of servers. If a DNS
server does not know how to translate a domain name, it will simply query another
DNS server until it finds one that can translate the domain name to the correct IP
address. Every server (a computer that offers services to other computers)
connected to the Internet has some information about domain names; DNS servers
keep huge lists of domain names matched with their IP addresses. Invisible to us the
Internet users, the domain names are converted to their numerical addresses using
the tables on DNS servers, and we get to where we want to be.
~'Web Tip
For a more detailed explanation of the Domain Name
System/Service see:
The Domain Name Service
http://www.scit.wlv.ac.uk/-jphb/comms/dns.html
DNS and BIND, 3rd Edition, O'Reilly Online Catalog
http://www.oreilly.com/catalog/dns3/chapter/ch02.html
Fortunately, there are many freely accessible tools for accessing and analyzing the
domain name system. Domain name and Whois lookup are among the most useful
tools available on the Internet. Many different kinds of tools are used for gathering
information about domain names and/or IP addresses. Before using these tools, it is
helpful to review how domain names and IP addresses work together to make it
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