You may have heard of the DNS server when you are connected to the Internet, which stands for Domain Name System, but what is it? A DNS server is a device that links the host name of the site to the IP address of the device hosting that site. In this article, we will find out about the types of DNS servers.
DNS Resolver
This is a computer used by Internet Service Providers (ISPs) to search the database for the name of the site requested by the user, and then direct the user to the IP address associated with the name, and it also plays a vital role in the operation of the DNS service. Click on this link to find out more https://www.tipsyoumustknow.com/ In addition, the DNS resolver stores data in the cache, for example the site example.com is currently on the machine that has the IP address 33.196.226.230, then all the decisions in the world will link the IP address as follows: example.com <- 33.196.226.230. So if the server hosting the site changes and has an IP address of 33.196.266.170, the memory of all the servers in the world will retain the old IP address for a while. This may cause the site to stop working for some time until the change is completely broadcast. The data stored in the DNS resolvers cache remains for a period of time called the time to live TTL.
Root DNS server
The central servers are the ones that have the addresses of all the top-level domain TLD servers, as the request first arrives at the central DNS servers on its journey to get the IP address of the requested site name. There are 13 central servers spread around the world as of 2016, and this does not mean that there are only 13 machines in the world to handle the massive requests from around the world, as there are several servers at local ISPs to handle these requests. Several organisations run central DNS servers and here is a list: top level domain TLD server, TLD servers pointing to authoritative name servers, authoritative DNS server.