Re: FW: New Version Notification for draft-hsingh-6man-enhanced-dad-01.txt

Also remember that 3697 is obsoleted by draft-ietf-6man-flow-3697bis,
which is fully approved and very close to becoming an RFC.

Regards
   Brian

On 2011-10-15 12:30, Tassos Chatzithomaoglou wrote:
> 
> Hemant Singh (shemant) wrote on 15/10/2011 01:41:
>> Tassos,
>>
>> From: Tassos Chatzithomaoglou [mailto:achatz@forthnet.gr]
>> Sent: Friday, October 14, 2011 6:29 PM
>> To: Hemant Singh (shemant)
>> Cc: IPv6 WG Mailing List
>> Subject: Re: FW: New Version Notification for
>> draft-hsingh-6man-enhanced-dad-01.txt
>>
>>
>>> I was wondering...wouldn't the flow label be a "better" field for
>>> storing this random number?
>>> If i remember correctly, early drafts of RPL were using it for loop
>>> detection (ok, in a very different way), although in the later ones a
>>> new option was chosen.
>>> Sure, RFC 3697 is very strict on its specification, sure SEND already
>>> uses the Nonce option, but since we are talking about ND only
>>> (=before any real src/dst flow) i would like to know the>rationale
>>> behind of this decision; choosing an extra option instead of a
>>> mandatory -useless until recently- field. Maybe then, all ND messages
>>> could be supported (less impact on memory?).
>>> I may have missed some talks about this in the past (or maybe i'm
>>> talking nonsense  :-[ ), so please forgive me if this is the case.
>> No forgiveness needed ☺.  You have been a great reviewer for lot of
>> documents!  The flow label was the first field I and another colleague
>> of mine at Cisco thought of.   However yet another colleague of mine
>> shot down the use of Flow Label with the following comments in double
>> quotes.
>>
>> “Using the flow label for this is likely to be highly controversial. 
>> I can already hear people claiming it's not a "flow", etc.”
>>
>> The flow label has another nuance.  It's a 20-bit field and thus a
>> nonce generated with such number of bits has one in a million chance
>> of a duplicate.  The community may prefer at least a 32-bit nonce or
>> higher.  That is why I decided to just use the Nonce Option from SEND
>> in RFC 3971.
>>
>> Thus can we move away from the Flow Label and use the Nonce Option
>> from SEND?
>>
>> Thanks,
>>
>> Hemant
>>
>>
> That is ok with me. Just wanted to know the background story.;-)
> 
> 
> btw, draft-asati-v6ops-dad-loopback seems to be dealing with the same
> problem too (but from a different perspective). Section 3.2 of it is
> quite similar though.
> Are there any plans to merge these two docs? If not, will there be any
> references of each other?
> 
> PS: previous email came from my old address, so i messed things a little
> bit.
> 
> Regards,
> Tassos
> 
> 
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