Re: [pim] AD Review of draft-ietf-pim-bfd-p2mp-use-case-05

[Greg Mirsky <[e-mail]>]

Hi Mike, Stig, et al,
I am not aware of any undisclosed IPR related to this document.

Regards,
Greg

On Thu, Oct 7, 2021 at 1:44 PM Michael McBride <
[e-mail]> wrote:

> Hi Greg, authors,
>
>
>
> We also need each of the authors to formally acknowledge that there is no
> undisclosed IPR on the draft by simply replying to this email.
>
>
>
> Thanks!
>
> mike
>
>
>
> *From:* pim <[e-mail]> *On Behalf Of * Greg Mirsky
> *Sent:* Tuesday, September 14, 2021 3:39 PM
> *To:* Alvaro Retana <[e-mail]>
> *Cc:* [e-mail]; [e-mail];
> [e-mail]; [e-mail]
> *Subject:* Re: [pim] AD Review of draft-ietf-pim-bfd-p2mp-use-case-05
>
>
>
> Hi Alvaro,
>
> thank you for your feedback and suggestions. I'll start the new working
> version and will update it based on your comments. Looking forward to
> hearing from other LC reviewers.
>
>
>
> Regards,
>
> Greg
>
>
>
> On Tue, Sep 14, 2021 at 11:39 AM Alvaro Retana <[e-mail]>
> wrote:
>
> On September 9, 2021 at 8:09:24 PM, Greg Mirsky wrote:
>
>
> Greg:
>
> Hi!
>
> > I've updated the working version to follow your comments. I've removed
> > references to DR/BDR and, as a result, the reference to
> > draft-ietf-pim-dr-improvement. As you've pointed out in comments, a tail
> > detects the failure of the head and then follows procedures defined in
> RFC
> > 7661 as if that was the failure in PIM Hello protocol. I've decided to
> leave
> > the section about the use of p2mp in PIM DR Load Balancing as that
> mechanism
> > is defined in RFC 8775, well after RFC 7661 was published.
>
> That's ok.
>
> As I mentioned before, I think the part about the head not performing
> the function it started with should be generalized into §2.1 -- here's
> the text I'm suggesting as the penultimate paragraph:
>
>    If the head is no longer serving the function that prompted it
>    to be monitored, then it MUST cease including the BFD Discriminator
>    PIM Hello option in its PIM-Hello message, and it SHOULD shut down
>    the BFD session following the procedures described in Section 5.9
>    [RFC8562].
>
>
> I also still have a couple of items (see below) to talk about.  I am
> starting the IETF LC, so you can take them as LC comments.
>
> Thanks!
>
> Alvaro.
>
>
>
> (1) I think that this text in §2.1 is still problematic:
>
> 187        If the head ceases to include the BFD Discriminator PIM Hello
> option
> 188        in its PIM-Hello message, tails MUST close the corresponding
> 189        MultipointTail BFD session without affecting the PIM state in
> any
> 190        way.  Thus the tail stops using BFD to monitor the head and
> reverts
> 191        to the procedures defined in [RFC7761].
>
> The problem is that the BFD session may not have been started using
> the PIM Hello Option -- maybe it was manually provisioned, for
> example.  If that is the case then requiring (MUST) to close the
> session ignores the manual configuration.  I think the action should
> be recommended (SHOULD) instead.
>
>
> (2) Security Considerations.  Let's add an introductory paragraph (or
> at least a couple of sentences) to justify why there are no additional
> security considerations.  Something following this structure:
>
>    This document defines a way to accelerate the detection of a PIM
>    failure by using BFD.  The operation of either protocol is not
>    changed.
>
>