In the times when Internet was not bigger than 1000 hosts, all the nodes in the network relied on the single file called HOSTS.TXT that was containing list of host names and their IPs.
Today, this type of IP address association can be seen very rarely. Network is relying on the text file that looks similar to the one shown in Figure 1. The file contains fields for domain name, IP address, and additional field called Alias. Alias is a nickname for the host. Instead of writing full domain address, alias could be used. Note that it would work only within an organisation where domain is located. The host file also indicates localhost address. The localhost is written in both forms, first in IPv6, then in IPv4 form.
Figure 1. Simple host file.
Hosts file is stored locally on user machine. On Linux/UNIX machine it is located in /etc folder and is called hosts. On windows it can be found from Windows\System32\drivers\etc. File name is hosts.
Host file solution might be sufficient for small organisation, however, bigger companies rely on automated solution described in next article.
