Re: [v6ops] Implementation Status of PREF64

Simon <> Fri, 15 October 2021 14:17 UTC

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Date: Fri, 15 Oct 2021 15:17:30 +0100
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Subject: Re: [v6ops] Implementation Status of PREF64
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David Farmer <> wrote:

>>> Not to put too fine a point on it, but I have seen no argument against Android including standards compliance

> Mark Smith <> wrote:
>> DHCPv6 is not required. See BCP 220.

I actually had in mind a comment made some way up the thread that Android ignores the A bit in RAs. If so then that’s a blatant violation, not just of the standard, but also of the wishes/policies of network operators who may be fully within both the letter and spirit of RFCs/BCPs.

> Yes, DHCPv6 is not required for hosts to implement, but it is recommended by RFC8504/BCP220

"Consequently, all hosts SHOULD implement address configuration via DHCPv6”
This, and the text leading up to it is very clear - if you value interoperability at all then implement DHCPv6 client on your devices.

> But then again, networks providing general propose hosts with more than one IPv6 address is not required and is also only recommended by RFC7934/BCP204.
> So I think we have a standoff or deadlock, can we find a way to break it? How about we all agree to implement the IETF's recommendations in both cases? 
> Personally, I think they are both very good recommendations.

Agreed. It does seem quite simple really. So why is it so hard ?