What is DNS? (visite count : 2481)
(Domain Name System), which briefly called DNS is a hierarchical database of symbolic names to their IP is distributed over the entire network. The system established in 1984 and developed over the following years.
When you enter the site, you need to address it Bdanyd.drs web server web server IP address specified, it is difficult to remember the IP address, it can be the IP of Domin Name (which at the beginning of this article included We mentioned the symbolic name) used. For each IP is considered a Domin Name. For example, the IP address is 188.8.131.52 Google. You will have access to Google can use the IP address for www.google.com.
In DNS, the Internet addresses are distributed in databases that do not focus on a specific network. The translation method is called when an application is forced to make a connection, or IP address of a machine with a name like CS.ucsb.edu to obtain, first of all, a function library (Library Function) call services, the library function, "the analyst called» (Name Resolver) is said analyst .tab name, a symbolic address that should be translated, accepted as input parameters and then request a package (Query Packet) Method UDP production and the address of a server DNS (which is default) sends. All of the host machine, at least the IP address of the DNS server are available. This "local server" After the search, the corresponding IP address by a symbolic name returns. (The analyst's name) in the IP address of the application to find the address of the IP, the application can continue his operations. Search methods for analyzing a DNS domain name system, levels separated from the right to left in a hierarchical process, the server can be found at the corresponding level.. If the domain name is different from region to search for corresponding IP address will be different.
7 public domain, all three words are:
com. Owner is the name of the economic and commercial institutions. www.sony.com
edu. Owner is the name of one of the institutions or university. www.sharif.edu
gov. The name of America is dedicated to government agencies. www.whitehouse.gov
int. : The owner of one of the international organizations (such as UNESCO, FAO, ...) is. www.unicef.int
mil. The name America is particularly military facilities.
net. Owner is the name of the network service providers. www.pegah.net
org. Owner's name, public and non-profit organizations are considered. www.ieee.org
Internet domain names are very much defined that none of the seven three-letter domains not see them at the end. Usually at the end of these addresses a series of two-letter abbreviation for the country is that it addresses and its owner, is located in that country.
Each area can be divided into smaller areas, which is also called the second-level domain.