[159618] in North American Network Operators' Group
Re: Slashdot: UK ISP PlusNet Testing Carrier-Grade NAT Instead of IPv6
daemon@ATHENA.MIT.EDU (Sander Steffann)
Wed Jan 16 15:15:46 2013
From: Sander Steffann <sander@steffann.nl>
In-Reply-To: <50F70524.4020102@fredan.se>
Date: Wed, 16 Jan 2013 21:15:21 +0100
To: fredrik danerklint <fredan-nanog@fredan.se>
Cc: North American Network Operators' Group <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Hi,
> If I have calculated the netmasks right that would mean to set aside:
>=20
> 2001:0DB8:6440::/42
>=20
> for the use of 6rd service:
>=20
> 2001:0DB8:6440:0000::/64 =3D 100.64.0.0
> ....
> 2001:0DB8:647F:FFFF::/64 =3D 100.127.255.255
You probably should add a few extra bits for subnetting behind the 6rd =
CPE. Delegating one /64 would be annoying as more and more CPEs have =
separate home/office/guest networks. Giving a /56 to each customer would =
be good and would only take an IPv6 /34 to map from 100.64.0.0/10. That =
is a quarter of the smallest IPv6 allocation an ISP can get.
ISPs can get plenty of IPv6 address space these days if they need it. =
Smaller ISPs don't need to map the whole 100.64.0.0/10, they could just =
start with 100.64.0.0/16 for example, which would only take a /40 to =
give every customer a /56. More blocks can always be added to the 6rd =
setup later.
Cheers,
Sander
