Re: [Detnet] WG Last Call: draft-ietf-detnet-bounded-latency-02

Dangjuanna <> Thu, 18 February 2021 07:27 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 5C5B03A0CB4 for <>; Wed, 17 Feb 2021 23:27:10 -0800 (PST)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -1.896
X-Spam-Status: No, score=-1.896 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id ifGuYn0RlyCs for <>; Wed, 17 Feb 2021 23:27:07 -0800 (PST)
Received: from ( []) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id A29CE3A0CB2 for <>; Wed, 17 Feb 2021 23:27:07 -0800 (PST)
Received: from (unknown []) by (SkyGuard) with ESMTP id 4Dh5h55P1Nz67pC9 for <>; Thu, 18 Feb 2021 15:20:05 +0800 (CST)
Received: from ( by ( with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2106.2; Thu, 18 Feb 2021 08:27:04 +0100
Received: from ( by ( with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Thu, 18 Feb 2021 15:27:02 +0800
Received: from ([]) by ([]) with mapi id 15.01.2106.006; Thu, 18 Feb 2021 15:27:02 +0800
From: Dangjuanna <>
To: "" <>, Lou Berger <>
Thread-Topic: Re: [Detnet] WG Last Call: draft-ietf-detnet-bounded-latency-02
Thread-Index: AdcFwybXhgkwiYVeQt2zcN5pnTEK+QAAZnNA
Date: Thu, 18 Feb 2021 07:27:02 +0000
Message-ID: <>
References: <>
In-Reply-To: <>
Accept-Language: zh-CN, en-US
Content-Language: en-US
x-originating-ip: []
Content-Type: multipart/alternative; boundary="_000_6d9fa11d2b8449808adfaccea96370aehuaweicom_"
MIME-Version: 1.0
X-CFilter-Loop: Reflected
Archived-At: <>
Subject: Re: [Detnet] WG Last Call: draft-ietf-detnet-bounded-latency-02
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Discussions on Deterministic Networking BoF and Proposed WG <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Thu, 18 Feb 2021 07:27:10 -0000

Dear All,

I've read carefully this draft version of the draft and support progressing it to the publication as the Informational RFC.

I attach great importance to the CFQ mechanism in Chapter 6.6  which can effectively decrease even eliminate the jitter problems to achieve the better E2E bounded latency assurance ,  and think it should be flexibly applied to Layer 2 or Layer 3. Currently CFQ with two buffers has been mostly discussed, but, from the aspect of improving the bandwidth utilization and getting better bounded latency aspect, CFQ with more than two buffer is one better kind of approaches to deploy in Detnet network. So I think the deployment, mechanism and packet format related to  CQF with more buffers need to be standardized in future.

So I suggest to enrich several non-blocking comments for the author's consideration as follows.

- For a large DT, CQF with more buffers can be used(Current words). Due to the variation of DT, a time interval in T_c cannot be used to send packets in this class; otherwise the receiving node cannot distinguish which cycle the packets belong with. As the results, the bandwidth utilization is limited especially when T_c is small. Using explicit cycle labels in packets can help resolves this ambiguity, so that bandwidth utilization and small T_c can be simultaneously achieved. The mechanism, packet format and per-hop behavior related to explicit cycle labels need to be further studied and standardized.



On Fri, Feb 5, 2021 at 5:30 AM Lou Berger <><mailto:&lt;;> wrote:

> All,


> This starts working group last call on draft-ietf-detnet-bounded-latency-02



> The working group last call ends on February 19th.

> Please send your comments to the working group mailing list.


> Please note, there was an IPR disclosure against this document

> submitted on January 14, 2021, see

> While this disclosure came very late in the document life cycle,

> it appears the filing was also relatively recent (2019-10-16) and

> after the pre adoption IP call:



> Positive comments, e.g., "I've reviewed this document

> and believe it is ready for publication", are welcome!

> This is useful and important, even from authors.


> Thank you,

> Lou (DetNet Co-Chair & doc Shepherd)




> _______________________________________________

> detnet mailing list