Originally a file named HOSTS. How to host a pdf file online hosts file is one of several system facilities that assists in addressing network nodes in a computer network.

Unlike remote DNS resolvers, the hosts file is under the direct control of the local computer’s administrator. Unsourced material may be challenged and removed. Entirely blank lines in the file are ignored. This example only contains entries for the loopback addresses of the system and their host names, a typical default content of the hosts file. IP addresses, as shown on the first and second lines respectively. Each network node maintained its own map of the network nodes as needed and assigned them names that were memorable to the users of the system. There was no method for ensuring that all references to a given node in a network were using the same name, nor was there a way to read the hosts file of another computer to automatically obtain a copy.

The small size of the ARPANET kept the administrative overhead small to maintain an accurate hosts file. Network nodes typically had one address and could have many names. This may be achieved by adding entries for those sites to redirect requests to another address that does not exist or to a harmless destination. Commercial software applications may be used to populate the hosts file with entries of known undesirable Internet resources automatically. The hosts file may present an attack vector for malicious software. Cisco Networking Academy Program: First-Year Companion Guide”, Cisco Systems, Inc. Microsoft KB 972034 Revision 2.