[117921] in North American Network Operators' Group
RE: ISP customer assignments
daemon@ATHENA.MIT.EDU (Lee Howard)
Tue Oct 6 10:22:02 2009
From: "Lee Howard" <lee@asgard.org>
To: "'William Herrin'" <herrin-nanog@dirtside.com>,
"'Brian Johnson'" <bjohnson@drtel.com>
In-Reply-To: <3c3e3fca0910050958q205eebf5r8fd761335afc1d70@mail.gmail.com>
Date: Tue, 6 Oct 2009 10:21:08 -0400
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
> -----Original Message-----
> From: William Herrin [mailto:herrin-nanog@dirtside.com]
> Sent: Monday, October 05, 2009 12:58 PM
> To: Brian Johnson
> Cc: nanog@nanog.org
> Subject: Re: ISP customer assignments
>
> /60 - the smallest amount you should allocate to a downstream customer
> with more than one computer. Anything smaller will cost you extra
> management overhead from not matching the nibble boundary for RDNS
> delegation,
I have a lack of imagination, I guess. I can't imagine anyone larger than
a small residential user being assigned a /60 or less. Therefore,
nybble boundary for rDNS delegation only matters if you delegate
rDNS for that block.
> handling multiple routes when the customer grows, not
Any customer getting a /60 or less will be dynamically numbered
(RA, DHCPv6, whatever), and if more space is needed, should be
easily renumbered into a larger prefix.
> matching the standard /64 subnet size and a myriad other obscure
> issues.
I don't know about "myriad" but I agree that /64 is the standard
subnet size.
I am *not* advocating assignments of /60 or less, just pointing
out that if you do it, it doesn't have to break.
Lee
