Sipcalc is an advanced console-based IP subnet calculator. It can take multiple
forms of input (IPv4/IPv6/interface/hostname) and output a multitude of 
information about a given subnet.

Features include: - IPv4

 * Retrieving of address information from interfaces.
 * Classfull and CIDR output.
 * Multiple address and netmask input and output formats (dotted
   quad, hex, number of bits).
 * Output of broadcast address, network class, Cisco wildcard, hosts/range,
   network range.
 * The ability to "split" a network based on a smaller netmask, now also with
   recursive runs on the generated subnets. (also IPv6)

- IPv6

 * Compressed and expanded input and output addresses.
 * Standard IPv6 network output.
 * v4 in v6 output.
 * Reverse DNS address generation.