[101423] in North American Network Operators' Group
Re: Assigning IPv6 /48's to CPE's?
daemon@ATHENA.MIT.EDU (Mark Andrews)
Thu Jan 3 19:23:10 2008
Date: Fri, 4 Jan 2008 11:22:06 +1100 (EST)
From: Mark Andrews <Mark_Andrews@isc.org>
To: nanog@merit.edu
In-Reply-To: <D03E4899F2FB3D4C8464E8C76B3B68B001AB7722@E03MVC4-UKBR.domain1.systemhost.net>
Errors-To: owner-nanog@merit.edu
In article <D03E4899F2FB3D4C8464E8C76B3B68B001AB7722@E03MVC4-UKBR.domain1.systemhost.net> you write:
>
>> > I'd rather push for /48 and have people settle on /56 than push for=20
>> > /56 and have people settle on /64.
>>=20
>> Again, why the hang-up on 8 bit boundaries?
>
>Look, why are we arguing about this? Why not split
>the difference? If /48 is too big and /64 is too small,
>let's go halfway and use /56, OK?
>
>This has the advantage that it is on a 4 bit nibble=20
>boundary which makes it the boundary between network
>and interface much clearer in writing
>2001:3ff3:effe:1200::0/56=20
>If you wrote 2001:3ff3:effe:12a0::0/56 then I would=20
>immediately see that there are too many bits in the network
>portion. It also avoids a messy situation with reverse
>DNS delegations.
And /48 is easier still.
2001:3ff3:effe:1234:xxxx:xxxx:xxxx:xxxx
<--ASSIGNED-->:<ME>:<------auto------->
>In the end, the decision had to be made to but the boundary
>somewhere, and with 16 bits to be divided plus the need to
>use 4-bit boundaries, the choices were (4,12), (8,8), and
>(12,4). Split the difference was the least objectionable.
>
>ARIN's decision on this boundary point has since been accepted
>by two other RIRs, so it seems to be community consensus now.
>
>--Michael Dillon
