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Website Development & Hosting

Examples of Domain Names

The naming system on which DNS is based is a hierarchical and logical tree structure called the

domain namespace. Domain names consist of individual labels separated by dots. .or example:

mydomain.microsoft.com.

A  .ully  Qualified  Domain  Name  (.QDN)  uniquely  identifies  the  host s  position  within  the  DNS

hierarchical tree by specifying a list of names separated by dots on the path from the referenced

host to the root. The following figure shows an example of a DNS tree with a host called mydomain

within the microsoft.com. domain. The .QDN for the host would be mydomain.microsoft.com.

Source: Microsoft Corporation.

Note: In general, .QDNs have naming restrictions that allow only the use of characters a-z, A-Z,

0-9, and the dash or minus sign (-). The use of the period (.) is allowed only between domain

name labels (for example,  microsoft.com ) or at the end of a .QDN. Domain names are not

case-sensitive. 

The figure at the right shows part of the

Internet  domain  namespace,  from  the

root domain and top-level Internet DNS

domains,  to  the  fictional  DNS  domain

named  reskit.com  that  contains  a  host

(computer) named Mfgserver. 

Computers  and  DNS  domains  are

named  based  on  their  position  in  the

domain  tree.  .or  example,  because

reskit  is  a  subdomain  of  the  .com

domain, the domain name for reskit is

reskit.com. 

Source: Microsoft Corporation

Copyright  NESIS 2002

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