Re: [6tisch] MSF Shepherd review

Yasuyuki Tanaka <yasuyuki.tanaka@inria.fr> Fri, 06 December 2019 20:43 UTC

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To: Tengfei Chang <tengfei.chang@gmail.com>
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From: Yasuyuki Tanaka <yasuyuki.tanaka@inria.fr>
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Subject: Re: [6tisch] MSF Shepherd review
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Hi Tengfei,

How do we distinguish multiple MSF sessions?
What if two MSF sessions have a same "selected parent", and then one of 
them selects another selected parent? How many negotiated cells should 
be taken over to the new selected parent?

These are not covered by the current text, and I think they are out of 
the scope of MSF.

> This specification only describes how MSF works with one routing parent, which is phrased as "selected parent".

So, yes, I believe we should have this case only in the text. If we 
mention some other possibilities without concrete ideas to implement, 
they would just confuse future readers.

I think, Pascal has a different opinion.

Best,
Yatch