Re: question about draft-ietf-6man-rfc3484bis-06.txt and CommonPrefixLen()

Karl Auer <> Tue, 31 July 2012 00:08 UTC

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Subject: Re: question about draft-ietf-6man-rfc3484bis-06.txt and CommonPrefixLen()
From: Karl Auer <>
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Date: Tue, 31 Jul 2012 10:08:15 +1000
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On Tue, 2012-07-31 at 08:30 +0900, Arifumi Matsumoto wrote:
> In my understanding, there is no use to look at the interface id part
> also for source address selection as well as for destination address
> selection.
> DNS load balance issue is explicitly specified, because it is clear
> problem that we see.

Thanks, Arifumi, but I don't understand your point. You have not said
*why* "there is no use".

I do see the rationale for stopping the comparison at the prefix length
for *destination* address selection. I do not see the rationale for
doing so for *source* address selection.

Perhaps we need to distinguish between source address selection and
source address checking. I just made up that second term :-)

Source address selection is the process of choosing which source address
will be used in an outgoing packet.

Source address checking is the process, performed during destination
address selection, of looking to see which source address *would* be
selected if a given destination address were selected.

My question is about the first of these two, not the second. I don't see
how DNS load balancing affects the first.

Regards, K.

Karl Auer (

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