Every single device which is connected to the world wide web has a unique identifier called IP (Internet Protocol) address. This includes personal computers, web servers, smart phones, switches, and so on. The pool of addresses, that was introduced initially, has already been distributed, therefore the so-called IPv4 IP addresses are slowly getting replaced with IPv6 addresses. Every domain which opens an internet site has an IP record, which is the address of the server where it is hosted. Using the IPv4 system, the record is called A and it is made up of four groups of numbers from 1 to 255 split up with a dot, while in the IPv6 system it is called AAAA and it is made up of 8 sets of hexadecimal numbers i.e. this kind of records use numbers from 0 to 9 and letters from A to F. An example of an AAAA record is 2010:0c48:43d3:2142:1012:8c3a:2475:2435 and this format supports a substantially larger number of IPs when compared with the IPv4 format.