What is a DNS address?
Briefly indicate the meaning and importance of DNS for the Internet, it is no exaggeration to say that this is one of the foundations of the World Wide Web.
Absolutely any computer that has Internet access is characterized by its specific Internet protocol or IP, with the help of which individual computer networks are combined into a single worldwide network. As a rule, IP is a four-byte number and without determining the IP address of the computer, there will be no information flow from the Internet.
All these processes occur automatically and instantly, and due to the fact that the human brain, even the most unique in its capabilities, is practically unable to remember such a huge number of IP addresses, and a special technology has been developed that can facilitate the fate of Internet users. This technology received the abbreviation DNS – a service or domain name system (Domain Name System), which allows you to determine the IP addresses of resources by their domains and exchange network information.
In order to get as far as possible from special terminology and try to explain the basic functions of DNS in simple words, we can give analogies from non-virtual life and put everything in order.
So what does a person do when he is about to call someone? All available options:
You can try to remember the desired phone number.
Select the recipient from the list of subscribers in the telephone directory of the mobile.
If the conversation with the right person took place recently, you can use the outgoing calls log.
As an option, call the help desk.
You can select from your list of subscribers any acquaintance who may know the required number or this acquaintance can find it out from some other source.
Approximately the same actions are initiated on the computer (given that the IP address can be compared with a set of digits of a phone number) before you get to some website. The role of the DNS service in the above analogy is to find out the phone number with only the name of the subscriber. This is the main function of DNS.
What other features does DNS have? It is logical that if you can determine the address of a computer on the network, knowing only its name, then you can get the opposite information – find out the name of the computer, having its address.
Of course, there is no guarantee that if the computer name will definitely correspond to any particular address, it is not a fact that other names will not be listed at this address or some computer will be recorded at all. For understanding, we can again use the analogy with telephone numbers as an example: very often it happens that a telephone number is registered for one person and a completely different subscriber uses it. The parallels with real life in this case are even stronger. It turns out that computers also require some kind of “registration” on the network: some systems on the Internet, for example, anti-spam services, check the correspondence of the address and name, and if this is not established, then it is not recommended that the systems accept mail from such addresses in the category containing spam.
Now a little more about the domain name system. If we take the semantics of the word “Domain” as a basis, then this word can be translated into Russian in several meanings, indicating a zone, territory, district (if we consider the general features), sphere (activities), region (interests), field (legal) and etc. Thus, the word “domain” is usually used to denote certain specific features, moreover, these features may not necessarily be territorial. The word was liked by its versatility and began to be used to denote the hierarchy of names on the Internet, but in this case, “hierarchy” refers to areas of responsibility on the network.
Again, using simplicity of understanding the analogy of real life, we can give an example of a different hierarchy: Marina works in the sales department of the furniture company Uryupinsk. How can I briefly write down the address for all items in the hierarchy? Approximately as follows:
One line on the domain name system, a brief record of Marina’s manager’s computer, a single line entry would look like this: Marina.Sbyt.OOOMEbel.Uryupinsk.Russia. Points in this case separate specific zones of the hierarchy. All information is presented in one line and, in principle, everyone understands everything.
But the Internet doesn’t really like too many letters, and domains are usually written in Latin letters. Therefore, the resourceful system administrator of Mebel would quickly take for his company a domain name that completely matches the name of the company, if at that time it would be free, and now the computer address in a new form, by all the dns rules, the address would already look like marina .mebeli.ru.