Re: [Roll] some comments on draft-thubert-dao-projection-00.txt

"Pascal Thubert (pthubert)" <pthubert@cisco.com> Mon, 06 July 2015 08:36 UTC

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From: "Pascal Thubert (pthubert)" <pthubert@cisco.com>
To: Routing Over Low power and Lossy networks <roll@ietf.org>
Thread-Topic: [Roll] some comments on draft-thubert-dao-projection-00.txt
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Subject: Re: [Roll] some comments on draft-thubert-dao-projection-00.txt
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Hello Michael:

The draft indicates that the root knows some topological information from the non-storing DAO (it knows all about the DODAG).

Per RFC 6550, a path constructed by storing-mode DAO messages is directional, packets flow parent to child,  and we do not want to introduce confusion by changing any of that.
Thus the segment that is constructed from the segment egress to the ingress. 

It results that the segment is directional but not that it is necessarily flowing down the DADOG, this depends on how much information is available to the root or whatever PCE is used as a helper.

Cheers,

Pascal

> -----Original Message-----
> From: Roll [mailto:roll-bounces@ietf.org] On Behalf Of Michael Richardson
> Sent: lundi 6 juillet 2015 02:08
> To: Routing Over Low power and Lossy networks
> Subject: Re: [Roll] some comments on draft-thubert-dao-projection-00.txt
> 
> 
> > It would be good to make it clear which direction one counts the
> "segment"
> > to know which one is last.  I don't like "segment" here, I think it's
> > a routing path...  Could you define segment if you think it's the most
> > natural term to use.
> > (There are also some articles like "the" missing in places, btw)
> 
> I also realized yesterday that 6554/RH3, uses the term segment.
> 
> --
> Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software
> Works  -= IPv6 IoT consulting =-
> 
>