DOMAIN NAME SYSYTEM (DNS)

DOMAIN NAME SYSYTEM (DNS)

What is DNS ?

 

            Domain Name System (DNS) is a database system that translates a

 

computer's fully qualified domain name into an IP address

 

 

What is Fully Qualified Domain Name ?

 

Ø      A fully qualified domain name (FQDN) is the complete domain name for a specific computer, or host, on the Internet

 

Ø      A fully qualified domain name consists of a host and domain name, including top-level domain

 

For example, www.sso.hcl.com is the fully qualified domain name for the sso directory of HCL corporate services.

 

 

What is a Zone ?

 

                        DNS data is divided into manageable sets of data called zone. It contains name and ip address information about one or more parts of a DNS domain.

 

 

Zone Types ?

 

Ø      Forward lookup zone

Ø      Reverse lookup zone

 

 

What is forward lookup Zone ?

 

A forward lookup zone searches for an ip address based on a provided host name. In general it resolves the host name to ip address of the computer.

 

 

What is reverse lookup Zone ?

 

A reverse lookup zone searches for the host name based on the ip address.In general it resolves the ip address to host name of the computer.