Subject: [ippm] AD Review #2 of RFC8321bis

From: Martin Duke <[email-masked]>
Date: Tue, 15 Feb 2022 14:01:20 -0800

Hi Giuseppe,

This is looking good.

1) The one conceptual problem I'm having is what it means for a packet to
be "unmarked". If marking involves encapsulation, no problem: some packets
can simply not be encapsulated, or one can omit the header option or
whatever. But if it's passive measurement because there's a bit in the
header, this bit has to be set to something, right?  So how would one
mediate between flows that are to be measured or not measured in the latter
case?

2) Some minor rewording of the new fragmentation language in section 4.4:
OLD

Nodes that fragment packets within the measurement domain MUST NOT
replicate marks, but SHOULD mark the first fragment if they have the

capability to do so.

NEW

Nodes that fragment packets within the measurement domain SHOULD, if

they have the capability to do so, ensure that only one resulting

fragment carries the marking bit(s) of the original packet. Failure

to do so can introduce errors into the measurement.

I would propose the following steps.

A) address these points and publish draft-02. We'll save the diff to show
the delta between 8321 and 8321 bis.

B) Immediately reorganize the document as you intend and publish draft-03.

Then we'll take it through IETF Last Call.

Thanks
Martin

---

From: Giuseppe Fioccola <[email-masked]>
Date: Wed, 16 Feb 2022 13:03:05 +0000

Hi Martin,
Thank you for your review.
I will publish the revision -02 soon and then I will prepare revision -03.

Please find my answers inline tagged as [GF]

Regards,

Giuseppe

From: Martin Duke <[email-masked]>
Sent: Tuesday, February 15, 2022 11:01 PM
To: [email-masked]
Cc: IETF IPPM WG <[email-masked]>
Subject: AD Review #2 of RFC8321bis

Hi Giuseppe,

This is looking good.

1) The one conceptual problem I'm having is what it means for a packet to be "unmarked". If marking involves encapsulation, no problem: some packets can simply not be encapsulated, or one can omit the header option or whatever. But if it's passive measurement because there's a bit in the header, this bit has to be set to something, right?  So how would one mediate between flows that are to be measured or not measured in the latter case?

[GF]: Yes, can add some considerations. As you said, if marking is done in a dedicated option/encapsulation (as in all the existing cases), there is no problem. But, if it is used a bit in the header, we can recommend to use an additional flag or some out-of-band signaling to indicate if the measurement is activated or not.

capability to do so.

NEW

[GF]: Ok, I will revise the text as suggested.

A) address these points and publish draft-02. We'll save the diff to show the delta between 8321 and 8321 bis.

[GF]: Good plan!

Thanks
Martin