RE: New Version Notification for draft-akiya-bfd-seamless-alert-discrim-03.txt

[Gregory Mirsky <[e-mail]>]

Hi Nobo, Authors, et. al,
please kindly consider my comments:
*       Section 2. Why not to add these to draft-ietf-bfd-seamless-use-case document?
*       Section 2.1
o       use of S-BFD as inter-AS OAM. Perhaps this use case suggest need for BGP extension to advertise S-BFD discriminator(s).
o       Lack of control plane. MPLS-TP without control plane assumes centralized provisioning and I think it would be reasonable to expect that S-BFD can be administered in the same manner.
o       "To accommodate the two scenarios described ..." you've listed three - which one can be ignored? :)
*       Section 2.2
o       I don't think that IP OAM should be concerned with disjointness of paths taken by different OAM packets over ECMP if network is properly designed and IGP convergence time is not much bigger than OAM defect detection time. (Otherwise there's no reason to report and investigate what well could be false negative defect.)
o       I think that this section talks more about need of defect correlation.
*       Section 3
o       Have you considered Alert Discriminator as update to draft-ietf-bfd-seamless-base? Otherwise, if Alert Discriminator is not part of S-BFD base, not mandatory but optional, capability, then, I think, it must be advertised.
*       Section 5
o       I think that requirement to protect ones NEs from potential DDoS using Alert Discriminator is very serious operational limitation.

      Regards,
                Greg

-----Original Message-----
From: Rtg-bfd [mailto:[e-mail]] On Behalf Of Nobo Akiya (nobo)
Sent: Tuesday, October 21, 2014 2:48 PM
To: [e-mail]
Subject: New Version Notification for draft-akiya-bfd-seamless-alert-discrim-03.txt

Dear BFD WG,

The last of the S-BFD documents, and likely the most controversial one, has been updated and published.

In summary, let's reserve S-BFD discriminator zero(0) as the alert discriminator.

We'd appreciate comments.

Thanks!

-Nobo, ducking for cover


[snip]
A new version of I-D, draft-akiya-bfd-seamless-alert-discrim-03.txt
has been successfully submitted by Nobo Akiya and posted to the IETF repository.

Name:           draft-akiya-bfd-seamless-alert-discrim
Revision:       03
Title:          Seamless Bidirectional Forwarding Detection (S-BFD) Alert Discriminator
Document date:  2014-10-21
Group:          Individual Submission
Pages:          9
URL:            http://www.ietf.org/internet-drafts/draft-akiya-bfd-seamless-alert-discrim-03.txt
Status:         https://datatracker.ietf.org/doc/draft-akiya-bfd-seamless-alert-discrim/
Htmlized:       http://tools.ietf.org/html/draft-akiya-bfd-seamless-alert-discrim-03
Diff:           http://www.ietf.org/rfcdiff?url2=draft-akiya-bfd-seamless-alert-discrim-03

Abstract:
   This document defines the Alert Discriminator which operates on the
   Seamless Bidirectional Forwarding Detection (S-BFD), and Alert
   Discriminator Diagnostic Codes which operates on the Alert
   Discriminator.
[snip]