Re: [RTG-DIR] [sfc] Rtgdir review of draft-ietf-sfc-ioam-nsh-10

[Greg Mirsky <[e-mail]>]

Hi Mach,
thank you for your review and comments. I have some information that might
be useful in considering the text update you've suggested (top
copy-pasting):

Section 3,
"The O-bit MUST be handled following the rules in
[I-D.ietf-sfc-oam-packet]."


According to [I-D.ietf-sfc-oam-packet], a NSH-encapsulated packet with IOAM
will not be considered as OAM packet. Thus, it's better to state that "the
O-bit MUST NOT be set" for packet with IOAM header in this document.


I agree that for a packet with the IOAM header as defined in RFC 9197, the
O-bit should not be set. But in draft-ietf-ippm-ioam-flags
<https://datatracker.ietf.org/doc/draft-ietf-ippm-ioam-flags/10/>, the
Active flag is defined that, as I understand it, might create an active OAM
packet. Although the use of the Active IOAM flag in the NSH has not yet
been defined, it is plausible that someone someday might decide to do that.
With that said, I propose to keep that quoted text as-is. WDYT?

Regards,
Greg

On Sat, Aug 27, 2022 at 2:17 AM Mach Chen <mach.chen=
[e-mail]> wrote:

> Hello,
> I have been selected as the Routing Directorate reviewer for this draft.
> The Routing Directorate seeks to review all routing or routing-related
> drafts as they pass through IETF last call and IESG review, and sometimes
> on special request. The purpose of the review is to provide assistance to
> the Routing ADs. For more information about the Routing Directorate, please
> see http://trac.tools.ietf.org/area/rtg/trac/wiki/RtgDir
> Although these comments are primarily for the use of the Routing ADs, it
> would be helpful if you could consider them along with any other IETF Last
> Call comments that you receive, and strive to resolve them through
> discussion or by updating the draft.
>
> Document: draft-ietf-sfc-ioam-nsh-10
> Reviewer: Mach Chen
> Review Date: 2022-08-22
> IETF LC End Date:
> Intended Status: Standards Track
>
> Summary:
> I have some minor concerns about this document that I think should be
> resolved before publication.
>
> Comments:
> The draft is well written and easy to read.
>
> Section 3,
> "The O-bit MUST be handled following the rules in
> [I-D.ietf-sfc-oam-packet]."
>
> According to [I-D.ietf-sfc-oam-packet], a NSH-encapsulated packet with
> IOAM will not be considered as OAM packet. Thus, it's better to state that
> "the O-bit MUST NOT be set" for packet with IOAM header in this document.
>
> Major Issues:
> No major issues found.
>
> Minor Issues:
> Quoted from Section 2.2, last paragraph of RFC 8300, it says:
> "...Packets with Next Protocol values not supported SHOULD be silently
> dropped
>       by default, although an implementation MAY provide a configuration
>       parameter to forward them."
>
> With above requirement, when insert an IOAM header to a NSH-encapsulated
> packet, the encapsulating node MUST make sure that every nodes (e.g., SFF,
> SF) along the service path supports IOAM, otherwise, the packet will be
> silently dropped. IMHO, this should be discussed in the document to make
> this more explicit.
>
> Nits:
> None.
>
> Best regards,
> Mach
>
> _______________________________________________
> sfc mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/sfc
>