From nanog-bounces+bonomi=mail.r-bonomi.com@nanog.org Sun Nov 13 14:15:38 2011 From: William Herrin <bill@herrin.us> Date: Sun, 13 Nov 2011 15:13:37 -0500 Subject: Re: Arguing against using public IP space To: nanog@nanog.org
On Sun, Nov 13, 2011 at 11:38 AM, Robert Bonomi <bonomi@mail.r-bonomi.com> wrote:
On Sun, 13 Nov 2011 10:36:43 -0500, Jason Lewis <jlewis@packetnexus.com> wrote;
http://www.redtigersecurity.com/security-briefings/2011/9/16/scada-vendors-u...
Any article that claims a /12 is a 'class B', and a /16 is a 'Class C', is DEFINITELY 'flawed'.
Hi Robert,
Give the chart a second look. 192.168.0.0/16 (one of the three RFC1918 spaces) is, in fact, a /16 of IPv4 address space and it is, in fact, found in the old "class C" range. Ditto 172.16.0.0/12. If there's a nitpick, the author should have labeled the column something like "classful area" instead of "classful description."
In the 'classful' world, neither the /12 or the /16 spaces were referencble as a single object. Correct 'classful descriptions' would have been: "16 contiguous Class 'B's" "256 contiguous Class 'C's"