Domain Name Servers

(fluid mechanics) direct numerical simulation
(computer science) domain name system

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(Domain Name System) A system for converting host names and domain names into IP addresses on the Internet or on local networks that use the TCP/IP protocol. For example, when a Web site address is given to the DNS either by typing a URL in a browser or behind the scenes from one application to another, DNS servers return the IP address of the server associated with that name.

In this hypothetical example, WWW.COMPANY.COM would be converted into the IP address 204.0.8.51. Without DNS, you would have to type the four numbers and dots into your browser to retrieve the Web site, which of course, you can do. Try finding the IP of a favorite Web site and type in the dotted number instead of the domain name!

A Hierarchy

The DNS system is a hierarchy of database servers that start with the root servers for all the top level domains (.com, .net, etc.). The root servers point to authoritative servers residing within ISPs and companies that resolve the host names to complete the name resolution. Using the example WWW.COMPANY.COM, COMPANY.COM is the domain name, and WWW is the host name. The domain name is the organization's identity on the Web, and the host name is the name of the actual Web server within that domain (see WWW). See DNS records, reverse DNS, DDNS, HOSTS file, mDNS, ping, root server and WINS.

Getting a Web Page

Turning a URL in a Web browser into an IP address can take numerous queries. This is a simplified diagram because the original requester actually talks to each name server in turn, and there can be more name servers in between. A request can also be satisfied from a DNS cache along the way and not need to reach the authoritative server.

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is short for:

Meaning	Category
Database Of Names And Salaries	Business
Di Neutro Salicylic acid	Academic & Science->Chemistry
Did Not Show for appointment	Medical->Physiology
Did Not Start	Community->Sports
Digital Nervous System	Computing->General
Digital Network Services	Computing->Networking
Dinitrosalicylic Acid	Academic & Science->Chemistry
Direct Numerical Simulation	Academic & Science->Electronics
Directorate of National Security	Governmental->Military
Do Not Ship	Business->Products
Do Not Spit	Miscellaneous->Funnies
Do Not Stop	Governmental->Transportation
Do Not Surf	Community->Sports
Domain Name Service	Computing->General Computing->Drivers
Domain Name System	Governmental->Military Computing->Networking Internet
Don't kNow Squat	Governmental->Military

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Dns	dns 120
Dns_parking	denon dj dns 3500