Re: [tcpm] [Last-Call] Opsdir telechat review of draft-ietf-tcpm-yang-tcp-07

[Gyan Mishra <[e-mail]>]

Hi Michael

Responses in-line

On Sat, Jul 9, 2022 at 4:10 PM Scharf, Michael <
[e-mail]> wrote:

> Hi Gyan,
>
>
>
> Inline [MS]…
>
>
>
> *From:* Gyan Mishra <[e-mail]>
> *Sent:* Friday, July 8, 2022 8:05 PM
> *To:* Scharf, Michael <[e-mail]>
> *Cc:* Last Call <[e-mail]>; Robert Raszuk <[e-mail]>;
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]
> *Subject:* Re: [Last-Call] [tcpm] Opsdir telechat review of
> draft-ietf-tcpm-yang-tcp-07
>
>
>
>
>
> Hi Michael
>
>
>
> Responses in-line
>
>
>
> On Tue, Jul 5, 2022 at 4:39 AM Scharf, Michael <
> [e-mail]> wrote:
>
> Hi Gyan,
>
>
>
> If something is needed beyond the current scope of
> draft-ietf-tcpm-yang-tcp, interested contributors and in particular also
> owner of running code have to speak up in TCPM.
>
>  Gyan> Understood
>
> Multiple implementations of the TCP MIB (RFC 4022) exist, and thus it is
> reasonable to assume that a similar YANG model as proposed in
>  draft-ietf-tcpm-yang-tcp will also be implemented and not be a theoretical
> exercise only.
>
>     Gyan> Agreed
>
> But TCPM contributors were quite concerned about the lack of success of
> other, more advanced TCP-related MIBs, e.g. the extended statistics in RFC
> 4898.
>
>     Gyan> That would be all the more reason and justification to have a
> complete TCP Yang model that covers not just the TCP MIB which TCPM
> contributors see as lacking such as advanced statistics.  Also these very
> statistics is what myself, Robert and others in Routing Area feel is a MUST
> for tracking telemetry TCP state and windowing etc for any app such as BGP
> using TCP as well as compute node transactional tracking and zero window
> frozen window issues.
>
>
>
> [MS] I suggest to precisely describe these use cases and what would be
> required in a corresponding YANG model. Details about existing solutions
> (e.g., in router operating systems) may also help.
>

     Gyan> Agreed and will do.   I will work with Routing Area folks to put
together the use cases

> As a result, there is no TCPM consensus to work on YANG without a
> crystal-clear use case.
>
>    Gyan> I can provide more detail into the use cases for routing area
> which are concrete real word use cases
>
>
>
> [MS] Often, a presentation in a TCPM meeting is a good first step to
> trigger a technical discussion. Also, keep in mind that the protocol stacks
> in router operating systems may have characteristics different to client
> and server operating systems. So, a careful technical analysis may be
> needed.
>
      Gyan> Understood.  As Susan Hares mentioned I think IETF 114 would be
a good opportunity to discuss the use cases and framework for the new Yang
model.  I am a member of TCPM so can I present the routing area use cases
to get the initial discussion started?

> TCP-AO is such an example and therefore included in
> draft-ietf-tcpm-yang-tcp - and in this case the configuration is relatively
> similar in different OS, i.e., modeling is doable.
>
> Gyan> Understood
>
> A separate question is whether further use cases would have to be handled
> by draft-ietf-tcpm-yang-tcp or in an new I-D. Any significant change of the
> scope would first have to reach consensus in TCPM.
>
>     Gyan> I think it makes sense to put further use case TCPM to make the
> yang model useful to all.  As it stands today it is not.
>
>
>
> [MS] Nothing prevents TCPM from extending the model defined in
> draft-ietf-tcpm-yang-tcp in follow-up steps (e.g., by augmentation). Unless
> I miss something, I am not aware of anything inside
> draft-ietf-tcpm-yang-tcp that **prevents** further modeling, e.g., to
> address other use cases. Thus, at least to me, it would be a quite
> reasonable strategy to address further use cases in a separate document.
>
> Gyan> Understood.  So I agree now that we have a path forward.  We can
> proceed to sign off OPSDIR review for  draft-ietf-tcpm-yang-tcp ready for
> publication.  We can start on the follow up steps for augmentation in a new
> yang model that addresses further use cases.  We can  kick this discussion
> off with presentation in TCPM on routing area use cases.
>
> BTW, in my opinion we are here discussing cross-area work. As far as I can
> tell, cross-area work is not a low-hanging fruit in the IETF; at least it
> will require some time. That alone may be one reason to solve further use
> cases separately.
>
>  Gyan> Understood.  I think this discussion is worthwhile setting a a
> meeting to review next steps with this draft and have contributors and all
> interested parties involved
>
> [MS] It clearly makes sense for interested parties to speak up and engage
> in TCPM. Yet, I’d like to emphasize once again that addressing further use
> cases may not necessarily require changing the (relatively well-defined)
> scope of draft-ietf-tcpm-yang-tcp. IMHO, not all problems need to be
> solved in a single document.
>
>          Gyan> Agreed and understood.

> Michael
>
> Michael
>
>
>
>
>
-- 

<http://www.verizon.com/>

*Gyan Mishra*

*Network Solutions A**rchitect *

*Email [e-mail] <[e-mail]>*



*M 301 502-1347*