BIND's named.rev File

BIND's named.rev File

This file specifies the IN-ADDR.ARPA domain, which is used to translate IP addresses into names. Because Internet addresses do not fall within domain boundaries, this special domain was formed to allow inverse mapping. The IN-ADDR.ARPA domain for a station has four labels preceding it. These labels correspond to the four octets of an Internet address in reverse order. All four octets must be specified, even if an octet is zero.

For example, the Internet address 128.32.130.12 is located in the domain 12.130.32.128.INADDR.ARPA. This reversal of the address allows for the natural grouping of stations in a network.

An IN-ADDR.ARPA domain can also represent a network. For example, if the ARPANET is network 10, there is a domain called 10.IN-ADDR.ARPA.