[ipwave] IPv6-over-foo and Addressing Architecture (was Re: [Int-dir] Intdir early review of draft-ietf-ipwave-ipv6-over-80211ocb-34 - options for fe80::/10 vs fe80::/64)

[Suresh Krishnan <[e-mail]>]

Hi Alex,

> On Apr 11, 2019, at 7:53 AM, Alexandre Petrescu <[e-mail]> wrote:
> 
> Le 11/04/2019 à 13:38, Ole Troan a écrit :
>>>>> I actually don't know if "this ipv6-over-80211ocb spec needs
>>>>> to rely on the use of a non-0 value in the intermediate 54
>>>>> bits", btw. If that's not the case, it's much safer and less
>>>>> controversial to just not mention it (either in the form of "LL
>>>>> prefix length" or more explicitly).  I guess that's also what
>>>>> others are suggesting (and I agree with them in that sense).
>>> There is the option of being silent about the prefix length of IPv6
>>> LLs in the IPv6-over-OCB document.
>>> There is the option of mentioning "fe80::/10", but with "Updates
>>> 4291 section X" in the header of the 1st page.
>>> There is the option of proving by implementation that fe80:1::1/32
>>> on OCB is not harmful to others.
>> Two of these options will likely prohibit consensus being reqched on
>> this document. I encourage you to carefully consider how to best
>> spend your time and the time of the particpants in the involved set
>> of working groups.
> 
> YEs, thank you for the advice Ole.  I need to take care how to spend my time.  Maybe try to avoid taking on directions that are known to be dead ended.
> 
> I read your message as a warning that I take seriously.  For that, I would like to ask you whether you make this suggestion as a WG Chair of 6man WG?  Or as a contributor to other WGs?

<AD Hat On>
I would like to look at this from a different angle. It is clear from the current standards that you need to be using fe80::/64 to form the LL address as the IPv6 address architecture requires the IID to be 64 bits long (for non b000 prefixes) and SLAAC requires the prefix and the IID lengths to add up to 128. If you want this changed, I don’t think this is the document where you should do it. The *burden of proof is on you* to show why the status quo does not work in this case and IMHO it has not been meet. 

I would request that you keep the link-local prefix length discussion out of this draft, and in 6man where it belongs. Here is the thread that you started in January this year in 6man

https://mailarchive.ietf.org/arch/msg/ipv6/SD0OSOxFe9UGExX84u_CQSdfOsM

and the associated draft

https://datatracker.ietf.org/doc/draft-petrescu-6man-ll-prefix-len/

If you wish to pursue this topic further, please do so with *that* draft. An IP-over-foo document is not a place to do such a major architectural change.

Thanks
Suresh