Re: [Detnet] draft-geng-detnet-requirements-bounded-latency-02 revised for comments

["qiangli (D)" <[e-mail]>]

Hi Peter,

Referencing ITU standards is acceptable IMHO. Let's see others' opinion.

Best regards,

Cristina QIANG

From: [e-mail] [mailto:[e-mail]]
Sent: Thursday, June 27, 2019 6:59 PM
To: qiangli (D) <[e-mail]>; [e-mail]
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Subject: RE: draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Cristina,

Personally I think it would be useful to reference such ITU standards if it does not cause IETF procedure issues.

Best Regardsyyo
Peter.

From: qiangli (D) <[e-mail]<mailto:[e-mail]>>
Sent: 27 June 2019 10:26
To: Willis,PJ,Peter,TUD1 R <[e-mail]<mailto:[e-mail]>>; [e-mail]<mailto:[e-mail]>
Cc: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>
Subject: RE: draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Hi Peter,

The relationship between clock jitter& wander and packet jitter is very complicated, varies a lot depend on different mechanisms. I know there are some time synch stands such as G.8273.2, G.8262. Is it helpful to reference this stands?


Best regards,

Cristina QIANG

From: [e-mail]<mailto:[e-mail]> [mailto:[e-mail]]
Sent: Wednesday, June 26, 2019 6:20 PM
To: [e-mail]<mailto:[e-mail]>; qiangli (D) <[e-mail]<mailto:[e-mail]>>
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Subject: RE: draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Colleagues,

>From a network operator's point of view I do not want the extra cost of highly accurate clocks in routers so prefer Detnet to work with the current clocks I have in routers. For an exact specification we would have to list the clock specifications in the typical routers that network operators use (it's not information I have at my fingertips).

I also put this requirement in to test what assumptions we are making about clock jitter & wander, and to check those assumptions are reasonable in practice. If there is a correlation between clock jitter & wander and packet jitter then that needs to be understood and stated.

Best Regards,
Peter.

From: Janos Farkas <[e-mail]<mailto:[e-mail]>>
Sent: 26 June 2019 10:37
To: qiangli (D) <[e-mail]<mailto:[e-mail]>>
Cc: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; Willis,PJ,Peter,TUD1 R <[e-mail]<mailto:[e-mail]>>; Liang GENG <[e-mail]<mailto:[e-mail]>>
Subject: RE: draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Hi Cristina,

Thank you for your quick response.

I'd like to have what others think.

Just one more note on my side: I think it depends a lot on the actual deployment/application/use case. For instance, in some cases, synchronization would be not needed at all; e.g., if the DetNet high availability / high reliability feature is what is really needed for the given case; or an asynchronous solution is used to achieve bounded low latency.

Best regards,
Janos

From: qiangli (D) <[e-mail]<mailto:[e-mail]>>
Sent: Wednesday, June 26, 2019 11:29 AM
To: Janos Farkas <[e-mail]<mailto:[e-mail]>>
Cc: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; Liang GENG <[e-mail]<mailto:[e-mail]>>
Subject: RE: draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Hello Janos,

Thanks for your kindly remind and comment. I copied the Req. 2.2 text as follows for easy check. The current version doesn't contain any solution and details as you requested. The reason that why we want to know what degree of clock jitter & wander DetNet can tolerate, is to detail the current text. According to your reply, I understand that DetNet just simply uses what is available.  So maybe we can simply list some existing standards here, no need to further specify more details. What do you think.

==========================================================
2.2.2.  Sub-requirement 2.2: Should tolerate clock jitter & wander
        within a clock synchronous domain

   DetNet domain itself can be time synchronous or asynchronous,
   depending on the technology selection of different operators.  Even
   within a time synchronous domain, the synchronized clocks may also
   experience jitter & wander, the mechanisms adopted by DetNet should
   be able to tolerate a certain degree of clock jitter & wander.
==========================================================

Best regards,

Cristina QIANG

From: Janos Farkas [mailto:[e-mail]]
Sent: Wednesday, June 26, 2019 4:28 PM
To: qiangli (D) <[e-mail]<mailto:[e-mail]>>
Cc: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; Liang GENG <[e-mail]<mailto:[e-mail]>>
Subject: RE: draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Hi Cristina,

My understanding of the consensus of the WG based on the Architecture document is that synchronization is acknowledged to be important; however, it is not the job of DetNet to specify the details, solutions, etc.; DetNet just uses what is available, specified by other standards.

Best regards,
Janos

From: detnet <[e-mail]<mailto:[e-mail]>> On Behalf Of qiangli (D)
Sent: Wednesday, June 26, 2019 5:33 AM
To: [e-mail]<mailto:[e-mail]>
Cc: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; Liang GENG <[e-mail]<mailto:[e-mail]>>
Subject: Re: [Detnet] draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Hi all,

The Req. 2.2 discusses that DetNet should be able to tolerate a certain degree of clock jitter & wander even within a time synchronous domain. We would like to know if you agree or disagree with this requirement. If you think this requirement is necessary, then to what degree of clock jitter & wander do you expect?

BTW, we are going to ask for WG adoption for this document in IETF 105 meeting. That's will be greatly appreciated if you can share your comments to help us further improve this draft.


Best regards,

Cristina QIANG

From: detnet [mailto:[e-mail]] On Behalf Of qiangli (D)
Sent: Monday, June 17, 2019 4:11 PM
To: [e-mail]<mailto:[e-mail]>
Cc: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; Liang GENG <[e-mail]<mailto:[e-mail]>>
Subject: Re: [Detnet] draft-geng-detnet-requirements-bounded-latency-02 revised for comments

Hi all,

This version has collected 7 requirements, and divided these requirements into optional (SHOULD) and mandatory (MUST) two types as following shows. We authors would like to know if this requirement list is complete, and if the classification is appropriate or not.  Your review and comments are highly appropriated.

==========================
Req. 1: Must support the dynamic creation, modification and deletion of deterministic services

Req. 2.1: Should support asynchronous clocks across domains
Req. 2.2 : Should tolerate a certain of clock jitter & wander within a clock synchronous domain

Req. 3: Must support Inter-Continental propagation delay

Req. 4: Should have self-monitoring capability

Req. 5: Should be robust against denial of service attacks

Req. 6: Must tolerate failures of links or nodes and topology changes

Req. 7: Must be scalable
===========================

Best regards,

Cristina QIANG

From: Liang GENG [mailto:[e-mail]]
Sent: Tuesday, June 11, 2019 11:53 AM
To: [e-mail]<mailto:[e-mail]>
Cc: Black, David <[e-mail]<mailto:[e-mail]>>; [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>; qiangli (D) <[e-mail]<mailto:[e-mail]>>
Subject: draft-geng-detnet-requirements-bounded-latency-02 revised for comments


Dear all,



Since IETF 104, we have carefully revised draft-geng-detnet-requirements-bounded-latency-02 according to received comments. The latest 02 version was uploaded and available online https://datatracker.ietf.org/doc/draft-geng-detnet-requirements-bounded-latency/.



This new version collects more technical, operational and management requirements of deploying deterministic latency service on layer 3 networks from the perspective of various service providers.



Comments are welcome!



Best regards,

Liang Geng on behavior of co-authors