[AusNOG] IPv6 Addressing

[Mark Smith]

On Tue, 5 Apr 2011 07:18:13 +0930
Mark Smith <nanog at 85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org>
wrote:

> On Mon, 4 Apr 2011 13:46:29 +0000
> Mark Grinceri <Mark at grinceri.com.au> wrote:
> 
> > Hi All,
> > 
> > I have received our IPv6 allocation from APNIC. Now the question is what is everyone doing for there point to point links /64, /126 or /127
> > 
> > From what I can gather most articles are just saying use /64, however I'm heading towards /126 but I'd like to know what the majority of IPv6 networks are assigning (ie Internode). I only want to do this once.
> > 
> 
> The idea behind using /64s for point-to-point links, and actually
> all links (see RFC4291), is both simplicity and having the same sized
> 64 bit interface identifiers for all end-nodes. If every link is a /64
> you can't make a prefix length mistake when typing it,

Of course that doesn't stop typos, but the typo will stick
out when it's not "64". If you have different prefix lengths then just
looking at the prefix length value won't tell you if it is correct or
incorrect, you'd have to be verifying it via something else e.g. an
IPAM system. Exceptions to the norm are where opportunities for error
creep in, so reducing exceptions reduces the chances for errors.

Regards,
Mark.