Re: [v6ops] draft-gont-v6ops-cpe-slaac-renum **Call for Adoption**

[Fernando Gont <[e-mail]>]

On 20/2/20 08:03, Mikael Abrahamsson wrote:
> On Thu, 20 Feb 2020, Fernando Gont wrote:
> 
>>      *  Any prefixes that were previously advertised via Router
>>         Advertisement (RA) messages for address configuration, but that
>>         are not currently intended for address configuration, MUST be
>>         advertised with a PIO with the "A" bit set to 1 and the "Valid
>>         Lifetime" and a "Preferred Lifetime" set to 0.
> 
> I think this is way too much text. Just say it should set the timers to 
> 0 and keep the flags, whatever they were. Writing this much prescriptive 
> language means there is a risk to get it wrong, or there is 
> misunderstandings.
> 
>>      *  Any prefixes that were previously advertised via RA messages as
>>         "on-link", but that are not currently not considered "on-link",
>>         MUST be advertised with a PIO with the "L" bit set to 1 and the
>>         "Valid Lifetime" and a "Preferred Lifetime" set to 0.
> 
> This can be rolled up into the previous paragraph.
> 
>>      *  If both of the previous conditions are met (a prefix was
>>         previously advertised with both the "A" and "L" bits set, but
>>         is currently *not* intended for address configuration and is
>>         *not* considered on-link), the prefix MUST be advertised with a
>>         PIO option with both the "A" and "L" bits set to 1 and the
>>         "Valid Lifetime" and a "Preferred Lifetime" set to 0.  That is.
>>         the advertisements of the previous two steps can be coalesced
>>         into a single one with both the "A" and "L" bits set.
> 
> Dito.
> 
>>      *  The aforementioned advertisement SHOULD be performed for at
>>         least the "Valid Lifetime" previously employed for such prefix.
>>
>> Thoughts?
> 
> Why not roll all of it up into:
> 
> "* Any prefixes advertised via RA MUST be announced with "Valid 
> lifetime" and "Preferred Lifetime" set to 0"

Point taken. How about:
'Any prefixes that were previously advertised via PIOs in Router 
Advertisement (RA) messages, and that have become stale, should be 
advertised with a PIOs that have both the "Valid Lifetime" and the 
"Preferred Lifetime" set to 0, and the A/L flags with the same settings 
as in the previous RA messages'


Not sure if "with the same settings" is clear enough, though.




> Guess if really needed, a sentence about "keeping A/L flags unchanged" 
> could be added.
> 
> L-13 in RFC7084 is short and sweet, why can't this one be similarily brief?

Agreed. Although L-13 of RFC7084 makes the reader assume what the proper 
settings for the flags are.


Thanks!

Cheers,
-- 
Fernando Gont
SI6 Networks
e-mail: [e-mail]
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