Re: problem statement [was Re: New Version Notification for draft-hinden-ipv4flag-00.txt]

Fred Baker <> Wed, 22 November 2017 00:35 UTC

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From: Fred Baker <>
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Subject: Re: problem statement [was Re: New Version Notification for draft-hinden-ipv4flag-00.txt]
Date: Tue, 21 Nov 2017 16:35:38 -0800
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I read through the thread and part of the draft. I think there is a fundamental issue.

>    This document specifies a Router Advertisement Flag to indicate that
>    there is no IPv4 service on the advertising router.

That doesn't tell the receiver anything about other routers, and especially IPv4-only routers that might exist in the environment. I don't think one can conclude from the receipt of an RA, or for that matter every RA from every IPv6-capable router in the environment, that there is no IPv4 service in the environment. One might conclude that from the lack of a response to a DHCP request for an IPv4 address. What I would expect the host to do is an exponential backoff to only asking for an address every mumble minutes, which would be lost in the noise.

I don't see the point.