[86389] in North American Network Operators' Group
Re: classful routes redux
daemon@ATHENA.MIT.EDU (Fred Baker)
Wed Nov 2 19:17:58 2005
In-Reply-To: <Pine.SOC.4.61.0511021600480.24185@paixhost.pch.net>
Cc: bmanning@vacation.karoshi.com,
Richard A Steenbergen <ras@e-gerbil.net>, nanog@merit.edu
From: Fred Baker <fred@cisco.com>
Date: Wed, 2 Nov 2005 16:17:28 -0800
To: Bill Woodcock <woody@pch.net>
Errors-To: owner-nanog@merit.edu
On Nov 2, 2005, at 4:01 PM, Bill Woodcock wrote:
> On Wed, 2 Nov 2005, Fred Baker wrote:
>> actually, no, I could compare a /48 to a class A.
>
> ...which makes the /32s-and-shorter that everybody's actually getting
> double-plus-As, or what?
A class A gives you 16 bits to enumerate 8 bit subnets. If you start
from the premise that all subnets are 8 bits (dubious, but I have
heard it asserted) in IPv4, and that all subnets in IPv6 are 16 bits
(again dubious, given the recent suggestion of a /56 allocation to an
edge network), a /48 is the counterpart of a class A. We just have a
lot more of them.
All of which seems a little twisted to me. While I think /32, /48, /
56, and /64 are reasonable prefix lengths for what they are proposed
for, I have this feeling of early fossilization when it doesn't
necessarily make sense.
