Re: [Roll] About merging two RFC drafts: draft-ietf-roll-enrollment-priority and DODAG size

["Pascal Thubert (pthubert)" <[e-mail]>]

Hello Huimin 

How does the Root figure the number of nodes? RPL does not give you that. But if everyone injects exactly the same number of routes (1?) then the dodag balancing that you want works just the same.

What would be the value of injecting the option in the middle of the network? What are the security considerations associated? 

Note that it is very hard to figure the load of a multipath several hops down and that routing based on load is prone to oscillation unless great care is given to the control system. Do you want to open that box?

All in all we want something simple, that does the work you need, and that is fully specified, no corner case, the we go smoothly through the review process.

Take care;

Pascal

> Le 7 févr. 2021 à 09:23, Huimin She (hushe) <[e-mail]> a écrit :
> 
> Hi Mikael,
> 
> I have added my name to the author list.
> 
> To Pascal and all,
> 1) I think the DODAG size represents number of nodes.
> 2) If the metric is introduced in the middle of the DODAG, how about setting the DODAG size to 0, meaning a useless number?
> 
> Best regards,
> Huimin
> 
> On 2021/2/7, 06:21, "Pascal Thubert (pthubert)" <[e-mail]> wrote:
> 
>    Hello Michael 
> 
>    There’s always room for future improvements. But do we necessarily need to point it out ? I’ve had to rewrite / remove similar text in recent IESG reviews and I now believe in focusing on what’s there not what could have been or may be one day.
> 
> 
>    Regards,
> 
>    Pascal
> 
>> Le 6 févr. 2021 à 22:56, Michael Richardson <[e-mail]> a écrit :
>> 
>> 
>> Pascal, thanks for starting this process!
>> I'm going to wait for Huimin to add his name to the author list, and
>> then I'll push an update document.
>> 
>> Your text puts both values into a single Metric.
>> I was thinking it would be two metrics, but upon reflection, it probably does
>> belong in a single metric object.
>> 
> 
>    Not sure what you mean by this. Same record ?
> 
>> What would an appropriate default be if the metric is introduced in the
>> middle of the DODAG?
>>  https://datatracker.ietf.org/doc/html/draft-ietf-roll-enrollment-priority-03#section-2.1
>> 
>> 
> 
>    Not sure it should be ; that’s the text I commented out and wanted to discuss with you. My initial understanding was that it didn’t happen but rereading I found the text allowed it. Same as above allowing that it is injected in the middle raises many questions for which I have no answer like on which occasion that happens, and what sense it makes. Eg the dodag size cannot be invented by a node in the middle; realistically not can a meaningful priority for the same reasons.
> 
> 
>> 
>> doc> The size of the DODAG is measured by the Root based one the DAO
>> doc> activity. It represents a number of routes not a number of nodes, and
>> doc> can only be used to infer a load in an homogeneous network where each
>> doc> node advertises the same number of addresses and generates roughly the
>> doc> same amount of traffic
>> 
>> I really that we would measure in terms of number of routes.
> 
>    You mean nodes not routes? Sadly we have no way to know that, do we?
> 
> 
>> 
>> pt> I'm concerned that the undocumented/future behavior will create comments
>> pt> at the IESG.  My observation is that we should either define the process
>> pt> fully or not mention it at all.
>> 
>> I concur that we will get comments, and yet, I think that we really do want
>> to allow for "future work".
> 
>    More than comments; they ask for crisp specification, backward compatibility and security issues...
> 
>    Take care,
> 
>    Pascal 
>> 
>> --
>> Michael Richardson <[e-mail]>   . o O ( IPv6 IøT consulting )
>>          Sandelman Software Works Inc, Ottawa and Worldwide
>