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Shortest Path First (SPF) Back-Off Delay Algorithm for Link-State IGPs
RFC 8405

Yes

(Alia Atlas)

No Objection

Alvaro Retana
Warren Kumari
(Alissa Cooper)
(Ben Campbell)
(Benoît Claise)

Note: This ballot was opened for revision 07 and is now closed.

Alvaro Retana (was Discuss) No Objection

Warren Kumari No Objection

(Alia Atlas; former steering group member) Yes

Yes (for -07)

                            

(Spencer Dawkins; former steering group member) Yes

Yes (2018-02-21 for -07)
I really like that you've produced this document. It was clear to someone with a minimal routing background. Thanks for that, too. 

I would support either Alvaro's Discuss or Deborah's Discuss, and maybe both.

- I think the document would still be useful if it was Informational, as an example of the kind of thing that could be done.

- If you really want stuff in the same network, or the same level/area, to use the same timers, putting safe-ish default values in the document would be more likely to make that happen.

I did notice one piece of text that wasn't clear to me. I found this confusing -

  In general, when the network is stable, there is a desire to compute
   a new Shortest Path First (SPF) as soon as a failure is detected in
   order to quickly route around the failure.  However, when the network
   is experiencing multiple temporally close failures over a short
   period of time, there is a conflicting desire to limit the frequency
   of SPF computations.  Indeed, this allows a reduction in control
   plane resources used by IGPs and all protocols/subsystems reacting on
   the attendant route change, such as ...

"this allows" seemed as likely to refer to the desire to limit, as anything else. Perhaps 

   ... limit the frequency
   of SPF computations, which would allow a reduction in control
   plane resources used by IGPs and all protocols/subsystems reacting on
   the attendant route change, such as ...

might be clearer.

(Adam Roach; former steering group member) No Objection

No Objection (2018-02-21 for -07)
Six authors seems excessive for a 13-page document. See RFC 7322 §4.1.1 for
guidance. If justified, I would expect to see a request for an exception to
the five-author rule in the ballot, or at least in the shepherd's write-up.

I support Deborah's DISCUSS.

I find a minor editorial nit in §7:

>  In general, the SPF delay algorithm is only effective in mitigating
>  micro-loops if it is deployed, with the same parameters, on all
>  routers, in the IGP domain or, at least, all routers in an IGP area/

"...on all routers in the IGP domain..." (remove comma)

(Alissa Cooper; former steering group member) No Objection

No Objection (for -07)

                            

(Ben Campbell; former steering group member) No Objection

No Objection (for -07)

                            

(Benoît Claise; former steering group member) No Objection

No Objection (for -07)

                            

(Deborah Brungard; former steering group member) (was Discuss) No Objection

No Objection (2018-03-13 for -09)
Thanks for addressing my comments.

(Eric Rescorla; former steering group member) No Objection

No Objection (2018-02-20 for -07)
I see other people have noted Ben's secdir review. That deserves addressing.

(Kathleen Moriarty; former steering group member) No Objection

No Objection (2018-02-21 for -07)
Thanks for addressing Ben's SecDir review.  It appears that the changes are queued up and it would be appreciated to ensure they are in the approved version.
https://mailarchive.ietf.org/arch/msg/secdir/x9QCq2kZTmcP0_ZFeZrv_rs5Mmw

(Mirja Kühlewind; former steering group member) No Objection

No Objection (2018-02-19 for -07)
1) Probably an editorial issue: "... SPF_DELAY to be restored to INITIAL_SPF_DELAY. e.g., 3 seconds."
3 seconds? The previous text says INITIAL_SPF_DELAY should be very short, e.g. 0 milliseconds...?

2) Also editorial: it would be helpful to show the state diagram right at the beginning.

(Suresh Krishnan; former steering group member) No Objection

No Objection (2018-02-21 for -07)
Agree with Alvaro's DISCUSS regarding specifying reasonable defaults.

(Terry Manderson; former steering group member) No Objection

No Objection (2018-02-21 for -07)
I think Alvaro and Deborah have covered the situation well.