Advanced console-based ip subnet calculator

 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.