SlackBuildsOrg/network/ipcalc
..
ipcalc.info
ipcalc.SlackBuild
README
slack-desc

ipcalc takes an IP address and netmask and calculates the resulting
broadcast, network, Cisco wildcard mask, and host range. By giving
a second netmask, you can design sub- and supernetworks. It is
also intended to be a teaching tool and presents the results as
easy-to-understand binary values.