August 8, 2010

Nameservers: Name Service Protocol Implementation

ICANN Logo
In computing, a Nameserver (also spelled nameserver) consists of a program or computer server that implements a name-service protocol. It maps a human-recognizable identifier to a system-internal, often numeric, identification or addressing component.

For example, on the Internet, a special case of name servers, so called Domain Name System (DNS) servers, are used to translate a hostname or a domain name (for example, 'en.wikipedia.org') to its corresponding binary identifier (the IP address 145.97.39.155), or vice versa.

The Internet maintains two principal namespaces, the domain name hierarchy and the Internet Protocol (IP) address system. The Domain Name System maintains the domain namespace and provides translation services between these two namespaces. Internet name servers implement the Domain Name System. A DNS name server is a server that stores the DNS records, such as address (A) records, name server (NS) records, and mail exchanger (MX) records for a domain name (see also List of DNS record types) and responds with answers to queries against its database.

The top hierarchy of the Internet Domain Name System is served by the root name servers maintained by delegation by the Internet Corporation for Assigned Names and Numbers (ICANN).
Recursive and caching name server
In principle, authoritative name servers are sufficient for the operation of the Internet. However, with only authoritative name servers operating, every DNS query must start with recursive queries at the root zone of the Domain Name System and each user system must implement resolver software capable of recursive operation.


To improve efficiency, reduce DNS traffic across the Internet, and increase performance in end-user applications, the Domain Name System supports DNS cache servers which store DNS query results for a period of time determined in the configuration (time-to-live) of the domain name record in question. Typically, such caching DNS servers, also called DNS caches, also implement the recursive algorithm necessary to resolve a given name starting with the DNS root through to the authoritative name servers of the queried domain. With this function implemented in the name server, user applications gain efficiency in design and operation.

The combination of DNS caching and recursive functions in a name server is not mandatory, the functions can be implemented independently in servers for special purposes.

Internet service providers typically provide recursive and caching name servers for their customers. In addition, many home networking routers implement DNS caches and recursors to improve efficiency in the local network.

About the Author

Tomboy

Author & Editor

Has laoreet percipitur ad. Vide interesset in mei, no his legimus verterem. Et nostrum imperdiet appellantur usu, mnesarchum referrentur id vim.

Post a Comment

 
Iwebslog Blog © 2015 - Designed by Templateism.com