DNS, or Domain Name System is something you use every day and maybe you don't know it; as human beings it is easier to remember a name than a series of numbers, this is where the DNS comes in; DNS servers keep the relationship between a name and a number (IP address) which is what the servers really understand.
Likewise, they also help us to route to the closest server depending on our location (CDN Content Delivery Network), keep in mind that the same domain (address of our website) can have more than one IP address associated with it. Why does this occur? Pages with high traffic require more than one server to serve requests, these servers can be in different parts of the world and the DNS servers are responsible for routing the closest server depending on our location.
Another advantage of DNS is that the domain name can remain static (remain the same) in the event that we change our IP address, in which case we must inform (in case you have the domain with us) with in order for the update to be performed for the new routing.
How to know the IP of our Domain?
There are several ways to know the IP that is associated with a domain, you can use a search engine to find a page that does it, or find it yourself with a basic terminal command in Windows, Linux or MAC.
For Windows you must open a CMD window (Windows Key + R and type cmd), which is equivalent to opening a 'terminal' on Linux or MAC, this is the software in which you enter the command prompts.< /p>
After our window is open we must write the following command:
Access hierarchies for domain resolution
Access to information is done hierarchically, starting initially to resolve the local data domain name within the operating system, for Windows this is found in the following file:
IP addresses and domain names can be stored in this file, this is especially useful in the case of accessing pages within our local network.
The next step in the event that the domain is not found is to access the information from our internet provider (ISP); who generally has slave servers with domain and IP data stored, this data is constantly updated and having it available helps to have faster communication.
The last hierarchy are the primary or master servers, in case neither the local machine nor the ISP servers have the information to resolve the domain, a primary server will be used who will be in charge of supplying the last IP associated to the page we want to access.
Security has been improving in recent years, especially with the implementation of encrypted connections and authentication certificates that allow us to know if we are really accessing the page we want to reach.
However, there are still cases of fraud, where IP's are accessed (remember that a server on the Web always has an IP address but not necessarily a domain) of cybercriminals' servers in order to carry out phishing or theft of information, this is achieved with a man-in-the-middle attack in which the machine and the user are fooled into believing that a fake page is authentic; currently this is controlled with the implementation of DNSSEC (Domain Name System Security Extension).
Another information security issue arises in the server that we are using to resolve the addresses (there is the possibility of choosing our DNS server both in our router and in our network card), since some operators knowing your IP is storing the domains you visit for commercial purposes.
As can be seen, in internet access devices it is possible to configure the DNS server to be used; There are currently several servers of this type, depending on the region where you are, some will be faster than others, said domain resolution speed can generaterar greater or lesser connection speed, since the longer the server takes to resolve the address, the longer the connection time will be (this happens especially the first time we connect to a page, later cache data will be used). p>