Know How Domain Name Servers Work

Written by Pawan Bangar

Domain name Servers

Domain name Servers (DNS) are an important but invisible part ofrepparttar internet, and form one ofrepparttar 107787 largest databases on it. Each machine on an internet is assigned a unique address, called an IP address, which is 32 bit number and is expressed as 4 octets. The method user to represent these IP addresses is known as "dotted decimal Notation". A typical address looks like this:

It is very difficult to keep in mindrepparttar 107788 IP addresses of allrepparttar 107789 websites we visit daily, because it's not easy to remember strings of numbers. However, we do remember words. This is where domain names come intorepparttar 107790 picture. If you want to connect to a particular site, you need to know its IP address but do need to know its URL. The DNS getsrepparttar 107791 mappings ofrepparttar 107792 IP addresses andrepparttar 107793 corresponding names.

Names and numbers

DNS convertsrepparttar 107794 machine names (such as to IP addresses (such as Basically, it translates from a name to an address and from an address to a name.

The mapping fromrepparttar 107795 IP address torepparttar 107796 machine name is called reverse mapping .when you type into your browser,repparttar 107797 browser first needs to getrepparttar 107798 IP address of The machine uses a directory service to look up IP addresses and this service is called DNS. When you type your machines firsts contacts a DNS server, asking it to findrepparttar 107799 IP address for This DNS server might then contact other DNS servers onrepparttar 107800 internet. DNS is therefore is considered asrepparttar 107801 global network of servers. The great advantage of DNS is that no organization is responsible for updating it. It is what is known as distributed database.

The three letter codes

A DNS server is just a computer that's runningrepparttar 107802 DNS software. The most popular DNS software is BIND (Berkeley Internet Name Domain) DNS is hierarchical, tree-structured system. The top is donated by'.'. And is known asrepparttar 107803 root ofrepparttar 107804 system. Belowrepparttar 107805 root there are seven immediate sub domain nodes and these are ‘com', ‘org', ‘gov', ‘mil', ‘net', ‘edu', ‘Int', etc.

DNS consists of two components •Nameserver. •Resolver.


This performsrepparttar 107806 task of looking uprepparttar 107807 names. Usually, there is one nameserver for a cluster of machines. Ifrepparttar 107808 nameserver does not containrepparttar 107809 requested information, it will contact another nameserver. But it is not required for every server to know how to contact every other server. Every nameserver will know how to contactrepparttar 107810 root nameserver, and this in turn will knowrepparttar 107811 location of every authoritative nameserver for allrepparttar 107812 second level domains.


This runs on a client machine to initiate DNS lookups. It contains a list of nameservers to use. As we have read,repparttar 107813 function of each of these nameservers is to resolve name queries. There are three types of nameservers-primary nameserver, secondary nameserver, and caching nameserver. The secondary nameservers are configured for backup purposes. Caching nameservers only resolve name queries but do not maintain any DNS database files. It is important to note here that any change to primary nameservers needs to be propagated to secondary nameservers. This is because primary nameservers ownrepparttar 107814 database records. The changes are propagated via a ‘zone transfer'.

Why to Adopt .Net

Written by Pawan Bangar

Why adopt .Net

•Websites and web services: For businesses to truly harnessrepparttar power ofrepparttar 107786 internet, websites must evolve. They must learn to interact with one another as well as with existing systems and applications. XML web services representrepparttar 107787 evolution ofrepparttar 107788 websites. •Integration: Takingrepparttar 107789 modular aspects of modern software applications and allowing them to communicate through standard internet protocols (XML & SOAP), XML Web services offer a direct means by which business processes and interact. •Reaching out: Creating XML web services and exposing them onrepparttar 107790 internet also provides another key advantage, it greatly expandsrepparttar 107791 number of customers and business partners that can come in contact with a business's services. •Rapid Development: Microsoft's Visual Studio .Net andrepparttar 107792 .Net framework empowers developers to quickly and easily create cutting-edge XML web services and applications building on their existing skills sets. Through multi-language support, developers are free to userepparttar 107793 appropriate language in building web services. In addition to their technical capabilities, these developer technologies help alleviaterepparttar 107794 greatest scarcity inrepparttar 107795 world: skilled programmers.

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