DNS servers are essential for the functioning of the web because they are the link between a website and an IP address.
What is a DNS server?
The DNS server (Domain Name System, or System of domain names in French) is a service whose main function is to translate a domain name into an IP address. To simplify, the DNS server acts as a directory that a computer consults when accessing another computer over a network. In other words, the DNS server is this service that makes it possible to associate with the website (or a connected computer or a server ) an IP address, as a telephone book makes it possible to associate a telephone number with a subscriber name.
Designed in 1983 by Jon Postel and Paul Mockapetris, the DNS is today essential in the world of web browsing. Each Internet service provider has, in particular, its own DNS servers, with IP addresses that often take the form of a succession of numbers of digits (126.96.36.199 for example).
The deposit of a domain name (of the type “mondomaine.com”) is carried out near a “registrar” (“ registrar ” in English), intermediary body between the applicants (or holders) of names of domain, and ICANN (Internet Corporation for Assigned Names and Numbers), a non-profit company responsible for the allocation of IP addresses worldwide via the domain name system.
The Domain Name System has therefore been set up to identify the different websites in a simpler way: it is a system of “translation” of IP addresses, addresses assigned uniquely to each machine connected to the Internet. (IP addresses are in a way analogous to telephone numbers).
The translation operation is called “name resolution (domain)” and must be perfectly mastered (just as a telephone number must lead to the establishment of good communication). It is ICANN’s role to ensure the proper resolution of names.
What is the difference between gTLDs and ccTLDs?
The Domain Name System (DNS) is a distributed directory based on a hierarchical name structure. The top of the hierarchy is the so-called “root” domain (administered by ICANN), from which branches emerge which are the so-called “top-level” domains, or, in English, the Top Level Domains (TLDs). Examples of TLDs are .com, .org, .net, .fr, etc.
There are gTLDs (generic Top Level Domains: .com, .org, .net, .biz, .info …) and ccTLDs (country code Top Level Domains: the national suffixes that are .fr, .ca, .nl, .es, .it …). TLDs are leaving new branches which are the so-called “lower level” domains (mondomaine.com for example).
Change of registrar
Once a domain name has been registered with a registrar (and the steps taken with the national body concerned in the case of a domain name whose suffix is a ccTLD), you may want to transfer the registration to the other registrar. During this procedure, the information relating to the domain name-IP address translation is kept during the transfer: any risk of service interruption is therefore avoided.
Change of host
More frequently, we will want to change the host, and we will have to transfer not the registration of the domain name but the destinations of the requests to this domain name.
If you have a domain name, you are listed as the administrative contact for this domain name registered with the registrar. As such, it is possible for us to modify the authoritative “DNS” for this domain.