Re: [Detnet] Opsdir last call review of draft-ietf-detnet-ip-oam-10

["Black, David" <[e-mail]>]

Hi Yingzhen,

Thanks for the review - it turned up a number of issues that are common with Bernard's review, so we decided to deal with his review first (see the recently posted -11) version and then look at this one.  In general, please take a look at the -11 version, which should be clearer.

David> Comments inline on specific items.

Thanks, --David

-----Original Message-----
From: Yingzhen Qu via Datatracker <[e-mail]> 
Sent: Friday, February 2, 2024 1:45 AM
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Subject: Opsdir last call review of draft-ietf-detnet-ip-oam-10


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Reviewer: Yingzhen Qu
Review result: Has Issues

Hi,

Thanks for the draft.

I am the assigned OPSDIR reviewer to conduct a last call review of this draft.

General comments:

The draft lists how existing OAM protocols/tools can be used in DetNet with IP
data plane. However, I don't think it's clearly stated in either the abstract
or the introduction section, so it's not clear to me what information the draft
is trying to deliver. OAM principles as stated in the abstract? or how existing
solutions may work in DetNet?

David> The latter is intended - this should be clarified and consistent in the -11 version, please check.

There are some editorial nits in the draft, and some of them made the draft
hard to read. I'd suggest an editorial pass and then I can do another round of
review.

Detail comments with line number from idnits:

80       usually performed on-demand. These tasks achieved by a combination
s/usually performed/are usually performed
s/achieved/are achieved

David> Fixed in the -11 version.

In Section 2.1, there should be a ":" after each term/abbreviation.

David> Agree, should be done for consistency.

145      packets. For example, that can be achieved with a 3-tuple
146      (destination and source IP addresses in combination with DSCP value)
147      used to identify the IP DetNet flow. In such a scenario, an IP OAM
148      session between the same pair of IP nodes would share the network
149      treatment with the monitored IP DetNet flow regardless of whether
150      ICMP, BFD, or STAMP protocol is used.

Q: Do you mean as long as two protocols, for example ICMP and BFD, have the
same DSCP value, the network treatment will be the same?

David> No, please see the new text in -11, which should be clearer.
In 20/20 hindsight, we omitted the assumption for the example that DetNet
is using 3-tuples (e.g., and not 5-tuples) to determine which traffic
receives DetNet handling/QoS.  The overall concern is that the OAM traffic
use the same network path and receive the same DetNet forwarding treatment
as the DetNet traffic that is being monitored.

158      protocol like, for example, UDP, a DetNet node must able to associate
s/must able to/must be able to

David> Ok, will fix.

168      protocol is one of the assigned by IANA, then the UDP source port can
s/the assigned/those assigned

David> Removed as part of rewriting that paragraph in -11.

167      DetNet flow. When the UDP destination port number used by the OAM
168      protocol is one of the assigned by IANA, then the UDP source port can
169      be used to achieve co-routedness of OAM, and the monitored IP DetNet
170      flow in the multipath environments, e.g., Link Aggregation Group or
171      Equal Cost Multipath.
Q: It's not clear how using the same UDP source port the OAM packets will be
guaranteed to follow the same path as the monitored IP flow. Please clarify.

David> Clarification/explanation improved in -11, please take a look at the new text.

266      and MPLS data planes analyzed in Section 6.2 of

268      [I-D.ietf-detnet-mpls-oam]. Also, requirements and recommendations
nits: broken line.

David> I suspect that's a tooling artifact, RFC Editor will deal with this.

268      [I-D.ietf-detnet-mpls-oam]. Also, requirements and recommendations
269      for OAM interworking between a DetNet domain with MPLS data plane and
270      OAM of a TSN equally apply to a DetNet domain with an IP data plane.
I'd suggest rewriting this sentence. I can't understand what it's trying to say.

David> Yes, it's a bit terse and unclear for that reason.  We'll propose new text in a subsequent message.

Thanks,
Yingzhen