Rfc 1924 describes a compact, fixed-size representation of ipv6 addresses which uses a base 85 number system. math::base85 handles some of the uglier details of it.

the base 85 numbers (from 0 to 84) are as follows:

0..9 a..z a..z ! # $ % & ( ) * + - ; < = > ? @ ^ _ ` { | } ~

at the moment, there's not much in this module. but it should be sufficient for the purposes of rfc 1924.

this module has a variable called $math::base85::base85_digits, which is a string containing the digits of the base 85 alphabet from lowest (0) to highest (~), in that order.