Re: [Roll] NSA PS-set metric/constraint

[Remous-Aris Koutsiamanis <[e-mail]>]

Hello Dominique,

sorry to bother you in a probably very busy period.
To finalise our draft before the cutoff, we're waiting for a brief answer
from you on this previous question:

On Sat, Feb 29, 2020 at 12:51 AM Remous-Aris Koutsiamanis <[e-mail]>
wrote:

>
> [DP] Alternate proposal:
>> Could the PS be part of an NSA Metric? After all, it is used to help
>> select which parent(s) are best suited for upward routing, not to prune
>> downlink propagation of the DIO along a path that exceed some metric
>> value. C=0, R=1, P=1 comes to mind for this metric.
>>
>
> [ARIS]
>
So I read a bit more about this. So C=0 means "use as a routing metric", OK.
> R=1 means "use as a recorded metric", i.e. not aggregated, because
> aggregated makes no sense, OK.
> Now, P=1 means that one or more of the nodes on the path did not record
> the metric. So, it's less a "command" and more a report of previous
> behaviour.
>
> My question is: it seems impossible that *all* the parent sets can be
> recorded along the path due to size, so each node *replaces* the received
> parent set with it's own.
>
> We can specify this with text of course, but I have not seen another
> existing metric that behaves like this.
> On the other hand, the NSA metric object is not used a lot, and if it
> makes sense for any metric to be replaced rather then appended to a list of
> metrics, that metric would be NSA.
>
> I am not sure about that P=1 part though and how it relates to replacing
> the existing metrics.
> If I understand this correctly, a node reporting it's own parent set in
> the NSA will set P=1 basically to let the receiving nodes know that they
> should not expect to find inside all the metric along the whole path, but
> only a part of it, and in our case from just the sending node.
>
> Am I getting this right?
>

Best,
Aris