Re: "RFC4941bis" and draft-gont-6man-non-stable-iids

[Suresh Krishnan <[e-mail]>]

Hi Tim,

> On Jul 19, 2017, at 6:00 PM, Tim Chown <[e-mail]> wrote:
> 
>> On 19 Jul 2017, at 13:57, Fernando Gont <[e-mail]> wrote:
>> 
>> On 07/19/2017 01:58 PM, Tim Chown wrote:
>>>> On 18 Jul 2017, at 15:52, Fernando Gont <[e-mail]>
>>>> wrote:
>>>> 
>>>> Folks,
>>>> 
>>>> Among the list of RFCs to be progressed to full std is/was RFC4941 
>>>> ("Privacy Extensions for Stateless Address Autoconfiguration in
>>>> IPv6").
>>>> 
>>>> As it stands, RFC4941 has a number of issues:
>>>> 
>>>> * Using the same IID for multiple prefixes * Not changing the IID
>>>> upon "security events" (including e.g., change in the underlying
>>>> MAC address) * Using MD5 as opposed to something better * Requiring
>>>> the use of temporary addresses along stable addresses (preventing
>>>> use of temporary-only, for nodes that feel like) * Not treating
>>>> IIDs as opaque values (see RFC7136)  when generating the randomized
>>>> IIDs (see step 3 in section 3.2.1 of RFC4941) * Mandating one
>>>> specific algorithm, when the same goals/properties can be achieved
>>>> with multiple algorithms (see section 4 of 
>>>> draft-gont-6man-non-stable-iids-01)
>>>> 
>>>> 
>>>> Based on the above, I personally don't think that it would make
>>>> sense to progress RFC4941 to Internet Standard, but rather think
>>>> that we should work on  a replacement of it -- our proposal being 
>>>> draft-gont-6man-non-stable-iids-01.
>>>> 
>>>> Thoughts?
>>> 
>>> Certainly any update on 4941 needs to be done in the light of a few
>>> deficiencies that have emerged over the years, and the publication of
>>> RFC7217.
>>> 
>>> I think it’s still possible to do a -bis off 4941.
>> 
>> My questions would be:
>> 
>> 1) Can you actually address the aforementioned deficiencies without
>> significant changes to RFC4941? -- It would seem to me that in order to
>> address them, rfc4941bis would not be a bis document anymore.
>> 
>> 2) If you were to address such deficiencies, could the bis document be
>> progressed to Internet Standard? -- My assessment of this question is: No.
>> 
>> If RFC4941 would take significant work, and the end result would
>> actually be significantly different from what's in RFC4941, then I'm not
>> sure that'd be different than starting from the I-D we already have...
> 
> Just to be clear, I like the material in your new draft.
> 
> That said, it seems you could do a similar style of update from 3041 to 4941, with a similar structure; the content is there in your draft, it “just" needs to be merged in.
> 
> That would mean obsoleting 4941, just as 4941 obsoleted 3041.  So you would include the details in 4941 that would carry forward.

<AD hat off>. I agree. If we are planning a drop in replacement to RFC4941 creating a bis document from there is the right thing to do.

Thanks
Suresh