Re: [dhcwg] Last Call: <draft-ietf-dhc-option-guidelines-14.txt> (Guidelines for Creating New DHCPv6 Options) to Best Current Practice

Ted Lemon <ted.lemon@nominum.com> Sun, 22 September 2013 14:16 UTC

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Subject: Re: [dhcwg] Last Call: <draft-ietf-dhc-option-guidelines-14.txt> (Guidelines for Creating New DHCPv6 Options) to Best Current Practice
From: Ted Lemon <ted.lemon@nominum.com>
In-Reply-To: <523B8255.7010902@chrysler.com>
Date: Sun, 22 Sep 2013 10:15:59 -0400
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References: <20130919215457.30925.98345.idtracker@ietfa.amsl.com> <523B8255.7010902@chrysler.com>
To: Kevin Darcy <kcd@chrysler.com>
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On Sep 19, 2013, at 7:01 PM, Kevin Darcy <kcd@chrysler.com> wrote:
> What would be the preferred way to provide a mixed list of IPv4 and IPv6 addresses, in a DHCPv6 option? IPv4-mapped addresses?

The preferred way would be not to do that.   I think there is a document floating around out there somewhere that uses IPv4-mapped addresses this way, but in general if you are configuring an IPv4 stack, you ought to be using DHCPv4.   Otherwise DHCPv6 winds up being a transition technology in perpetuum.

To be clear, you definitely should not expect a DHCPv6 client to do something meaningful with an arbitrary IPv4-mapped IPv6 address.   It's anybody's guess where this would clog the plumbing, but it almost certainly wouldn't work.