[101176] in North American Network Operators' Group
Re: v6 subnet size for DSL & leased line customers
daemon@ATHENA.MIT.EDU (Chris Adams)
Fri Dec 21 12:22:56 2007
Date: Fri, 21 Dec 2007 11:20:41 -0600
From: Chris Adams <cmadams@hiwaay.net>
To: nanog@merit.edu
Mail-Followup-To: Chris Adams <cmadams@hiwaay.net>, nanog@merit.edu
In-Reply-To: <002f01c843f5$5d3e1f60$17ba5e20$@net>
Errors-To: owner-nanog@merit.edu
Once upon a time, TJ <trejrco@tjevans.net> said:
> Short answer - no spec for it.
> ARIN breaks it at /56, as a nod towards maybe a /48 for everyone is
> a bit much.
On ARIN's site:
The following guidelines may be useful (but they are only guidelines):
* /64 when it is known that one and only one subnet is needed
* /56 for small sites, those expected to need only a few subnets
over the next 5 years.
* /48 for larger sites
For end sites to whom reverse DNS will be delegated, the LIR/ISP should
consider making an assignment on a nibble (4-bit) boundary to simplify
reverse lookup delegation.
So, the guidelines are on 8 bit boundaries, but then right below they
also suggest making assignments on 4 bit boundaries (and it is all "only
guidelines").
--
Chris Adams <cmadams@hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.
