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

Mikael Abrahamsson <> Mon, 20 November 2017 07:51 UTC

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Date: Mon, 20 Nov 2017 08:51:21 +0100 (CET)
From: Mikael Abrahamsson <>
To: Lorenzo Colitti <>
cc: Jen Linkova <>, IETF IPv6 Mailing List <>
Subject: Re: problem statement [was Re: New Version Notification for draft-hinden-ipv4flag-00.txt]
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On Mon, 20 Nov 2017, Lorenzo Colitti wrote:

> Sure. But you wouldn't need complicated infrastructure for this - if all 
> that's necessary is to respond to a DHCPv4 request with a canned "no 
> DHCPv4 here" packet that is always the same, that's a lot easier to 
> deploy than a full DHCPv4 infrastructure.

This functionality doesn't exist today in any access network I know of. 
It's also non-trivial to do considering how access networks are done. 
Preferrably one would like to ahve an ethertype filter on the access port 
to only allow 0x86dd and nothing else. Then putting this flag into IPv4 
means this isn't possible.

IPv6 is the next generation IP protocol. I prefer that it can signal that 
the legacy version is not available, instead of having to keep legacy IP 
functionality around.

... or we put it in some other L2 protocol, such as LLDP.

Mikael Abrahamsson    email: