IPv6 Subnet tool

[Drake Wilson]

Quoth Joe Abley <jabley at hopcount.ca>, on 2009-01-14 15:55:08 -0500:
> Maybe I'm just bitter about the number of v6 numbering plans I've rolled 
> out that map VLAN tags into those 16 bits from the bottom up, and map 
> non-VLAN things from the top down, starting at ffff :-)

You can still map those onto 8-bit representations so long as there
aren't too many; you just need to reset the dividing line.  If the
dividing line is in the middle, you can even imagine the bits to be
representations of two's-complement signed integers, and then 0000/9
and FF80/9 get translated to 00/1 and 80/1 by sign contraction.

   ---> Drake Wilson