DNSDNS, the Domain Name System, is a distributed database system designed to provide a name for address lookup to computers requesting information from the Internet. It is composed of two main components: a hierarchy and a name service. Hierarchy • responsible for structure, naming conventions, and delegation of authority • Provides a means of managing the distribution database system. DNS Name Service • Provides the actual name for the address mapping mechanism. Figure 1 Domain naming scheme • Follows the structure of the DNS hierarchy. • Can be defined as a list of all domains in the path from the local domain at the root.• Each level of the domain name is followed by a period, or period. o i.e. technet.microsoft.com. Is the domain name of the TechNet domain (see Figure 1). • The domain name is followed by a period. o This represents the root domain. o Known as Fully Qualified Domain Name (FQDN). The DNS Domain• Provides the label of the DNS tree.• Each node represents a domain.• The domains below the top-level domains are known as individual entities.• The top-level domains can be further divided into subdomains.• Manages information about an entity's host computers.• Domains located at the leaves of the tree generally represent individual hosts. DNS Hostname• Any computer that uses DNS• reflects the computer's position in the DNS hierarchy, that is, the DNS hostname for host 2 (see Figure 1) would be host2. technet.microsoft.com. Any domain in a subtree is considered part of all domains above it, hence technet.microsoft.com. The domain is part of the microsoft.com domain., which is part of the com domain. domain.• A fully qualified domain name can be up to 255 characters long, however some systems may have a smaller number like...... middle of paper ......org/topics/internet/48405289.jpg http://technet.microsoft.com/en-us/library/cc723704.aspx http://technet.microsoft.com/en-us/library/cc731204(v=ws.10).aspx http://support .microsoft.com/kb/232025/EN-US http://compnetworking.about.com/od/dns_domainnamesystem/f/what-is-a-dns-cache.htm http://technet.microsoft.com/en -us /library/Bb962069.tcpipm03_big(l=en-us).gif http://kb.iu.edu/data/aiuv.html http://www.techrepublic.com/article/know-how-to- distinguish- DNS query types/#. http://www.tech-forums.net/forums/f9/where-dns-cache-stored-64578/ http://www.youtube.com/watch?feature=player_detailpage&v=3EvjwlQ43_4 http://technet.microsoft .com/en-us/library/cc781340(v=ws.10).aspx http://www.zytrax.com/books/dns/ch8/ http://tools.ietf.org/html/rfc3596#section -2.1 http://tools.ietf.org/html/rfc2782 http://support.microsoft.com/kb/232025/EN-UShttp://it.med.miami.edu/x1111.xml