Re: IPv6 address assignment for strictly point-to-point links and Device Loopbacks

Brian E Carpenter <brian.e.carpenter@gmail.com> Fri, 21 September 2012 23:06 UTC

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Date: Sat, 22 Sep 2012 00:06:04 +0100
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
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To: Usman Latif <osmankh@yahoo.com>
Subject: Re: IPv6 address assignment for strictly point-to-point links and Device Loopbacks
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On 21/09/2012 22:35, Usman Latif wrote:
> Thanks Wes for the feedback.

...
>>>> Without this stated clearly there is likely to be some instances where readers interpret it the wrong way and end up assigning multiple p2p links with /127 subnets from a single given /64 and end up having to re-address their network in future when/if future standards use lower order 64 bits for special purposes.
>> [WEG] Given the fact that there is a standard that documents the use of a /127 for P2P links (6164), 

Wes, I think that statement is even a bit weak, since 6164 actually says:

"assuming that a number of point-to-point links will be numbered out of a single /64 prefix:"

so it is very clear: it is allowed by the standard to share a /64 among
however many pt2pt links the operator cares to. This is *not* a wrong
interpretation.

As you say, any future work will need to take account of this.

   Brian