Subject: [Gen-art] Genart last call review of draft-ietf-6tisch-msf-10

From: Vijay Gurbani via Datatracker <[email-masked]>
Date: Fri, 14 Feb 2020 08:42:36 -0800

Reviewer: Vijay Gurbani
Review result: Almost Ready

I am the assigned Gen-ART reviewer for this draft. The General Area
Review Team (Gen-ART) reviews all IETF documents being processed
by the IESG for the IETF Chair.  Please treat these comments just
like any other last call comments.

For more information, please see the FAQ at

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Document: draft-ietf-6tisch-msf-10
Reviewer: Vijay K. Gurbani
Review Date: 2020-02-14
IETF LC End Date: 2020-02-27
IESG Telechat date: Not scheduled for a telechat

Summary: The draft is almost ready to be published as a Proposed Standard.

Major issues: 1

Minor issues: 0

Nits/editorial comments: 1

Sn below stands for "Section n".

Major:

- S2, paragraph 4: The text says that "...a node implementing MSF SHOULD enforce
  some rules for limiting the traffic broadcast frames...".  It goes ahead and
  gives an example of the "Trickle" operation, but in the very next sentence, it
  says, "This behavior is out of the scope for MSF."  I am confused since the
  paragraph does not seem self consistent.

  The paragraph is asking the implementor to use normative strength (SHOULD) to
  enforce "some" rules, but does not enumerate the rules.  To be fair, the
  paragraph gives one example of such a rule, but immediately invalidates that
  example!  What would an implementor do?  Where would he or she go to get an
  idea of "some" rules that can be used to limit the traffic of broadcast
  frames? Perhaps some reference could be provided to a document that contains
  these rules? 

Nits:

 - S6: s/It is calculated/The timeout value is calculated/

Thank you.

---

From: Tengfei Chang <[email-masked]>
Date: Sat, 15 Feb 2020 14:35:16 +0100

H Vijay,

Thanks a lot for the review!

For the major comment, what we want to explain here is that there are
multiple way to limit traffic to lighten the collisions.
Trickle timer is one of those algorithm for that purpose.
What "*This behavior is out of the scope for MSF*." means here actually is
that we don't want to limit the various ways of limiting traffic by just
using Trickle timer.
The implementer can  design their own algorithm to mitigate the traffic
collisions on minimal cell.

The paragraph is rephrased as following:

*To ensure there is enough bandwidth available on the minimal cell, a node
implementing MSF SHOULD enforce some rules for limiting the traffic of
broadcast frames. *
*For example, the overall broadcast traffic among the node and its
neighbors **SHOULD NOT exceed 1/3 of the bandwidth of minimal cell.*
*One of the algorithm met the rule is the Trickle timer defined in
[RFC6206] which is applied on DIO messages [RFC6550]. *
*The algorithm of limiting the broadcast traffic to meet those rules is
implementation-specific and is out of the scope of MSF.*

Does this version sound clear for you?

Tengfei

On Fri, Feb 14, 2020 at 5:43 PM Vijay Gurbani via Datatracker <
[email-masked]> wrote:

> _______________________________________________
> 6tisch mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/6tisch
>

-- 
——————————————————————————————————————

Dr. Tengfei, Chang
Postdoctoral Research Engineer, Inria

www.tchang.org/
——————————————————————————————————————

---

From: Vijay Gurbani <[email-masked]>
Date: Sat, 15 Feb 2020 16:07:45 -0600

Dear Tengfei: Thank you for getting back to me and your time to address my
review.

The paragraph you suggest is very much improved, with one small change that
will make it even better, as described next.

In the last sentence of your proposed change, s/The algorithm of limiting
the/However, any such algorithm of limiting the/

Once again, thanks.

- vijay

On Sat, Feb 15, 2020 at 7:35 AM Tengfei Chang <[email-masked]>
wrote:

> What "*This behavior is out of the scope for MSF*." means here actually
> is that we don't want to limit the various ways of limiting traffic by just
> using Trickle timer.

---

From: Tengfei Chang <[email-masked]>
Date: Sun, 16 Feb 2020 01:17:49 +0100

Thanks for the suggestion! I will apply those changes in next the version
of MSF.

Tengfei

On Sat, Feb 15, 2020 at 11:07 PM Vijay Gurbani <[email-masked]>
wrote:

> The paragraph you suggest is very much improved, with one small change
> that will make it even better, as described next.
>
>> *To ensure there is enough bandwidth available on the minimal cell, a
>> node implementing MSF SHOULD enforce some rules for limiting the traffic of
>> broadcast frames. *

Dr. Tengfei, Chang

www.tchang.org/