Re: ISP customer assignments - and CIDR

On Oct 16, 2009, at 5:19 PM, Owen DeLong wrote:

I've taught both. If you try to teach it in Decimal, Hex, or Octal, you're right, it's hard to teach CIDR and easy to teach classful.

It really does not matter the representation as long as you divide your Address Pie with a Binary Knife. Once you understand that -- 1/2, 1/2 of 1/2, 1/2 of 1/2 of 1/2, ... -- then you should understand CIDR. Then, as Owen suggests, deal with the representation. Works for IPv4, IPv6, and, probably, IPv8. ;) Warning, strong opinion follows: One should never have to mention Classful addressing except to note that it is archaic, anachronistic, and used only by those who remain ignorant by preference. James R. Cutler james.cutler@consultant.com