From nobody Wed Apr 14 04:11:35 2021 Return-Path: X-Original-To: ipv6@ietfa.amsl.com Delivered-To: ipv6@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 0DFA33A1B6C; Wed, 14 Apr 2021 04:11:34 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -2.098 X-Spam-Level: X-Spam-Status: No, score=-2.098 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=unavailable autolearn_force=no Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2WZC41gszepx; Wed, 14 Apr 2021 04:11:28 -0700 (PDT) Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 1F9A83A1B6A; Wed, 14 Apr 2021 04:11:27 -0700 (PDT) Received: by mail-wm1-x329.google.com with SMTP id o21-20020a1c4d150000b029012e52898006so684492wmh.0; Wed, 14 Apr 2021 04:11:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=7A7PK6Rap26kS39WVVO1R4lBpyQf/9g7CKfH9H3PefQ=; b=te/E1ITPoWYz/q7iAso0oy6D2e8sNsSxIaf0YGt1pf2pvV0sdc8SS6flb6iNMo0+KZ 0Evf3crny+4H79mjulfoOMd+Xr4UYAQO79k0+uwsg+imG7aNbZ+8xqmZmFffTe99G9XT a/SEImklQ3lgCJVag/b13rKWIJqcBNZ4l3czXr8ww4GyHuSmUAclbK+So9VsaLUJmNcs AGJu2uCVcDzx4+r3GHPXcj6yYRUqBtsQcCgjqOc0au2I0OFma1qvQNzqLdYk3NnV7eBG 9Psp9PDe+RWWiDO/HSOVANxVFOxmBdil41CE+J4yLhVDICVYWWGOi1W521wG/rmVRwVR p4Zw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=7A7PK6Rap26kS39WVVO1R4lBpyQf/9g7CKfH9H3PefQ=; b=No1n7nCwxJsYB3eaefgti+GylwBJ1DQ2VHJU856O0MOyb15xOY/fAHSNQAUOxj9kQA ADGlTQBZy5HBPClJY0TCa6d5NoC6PYEF6zliQRl6HQrmym5GW4tzu6aKOMmGhWNOJA5j 2tf+tFEJgLQSQ2FpoWYQm9mLTkuityFVPksMRjVgKGflhfVbPhKezlkrwKrY5Jb+ErVG qb77IC4Yd/JyEZKvn5wpU2c3IGVORj7xepggzrsS/zGLGzekvjAh8Guex13DiMoMNl3z RPfccDr8xe42F8PqZWpoHCMsd6+s+jkJ+NIzSFNdnnmbW4XyFt+OCZ294BPT4FMsblmR dK2A== X-Gm-Message-State: AOAM530mmwPfjK7qHSfcjO0WNUP1OaJDpbU8Kljx9k2Jxr3lFp2oPN3x MiD1uCYt5Yvo0NMFtiDaigs= X-Google-Smtp-Source: ABdhPJyuYkwLPdJmRP848xKU2hFP96Gjt7hd7h7ncW/4HIp3IEMygED+iMTGNfvPYhwHgVuOBspAIg== X-Received: by 2002:a1c:f715:: with SMTP id v21mr2504001wmh.187.1618398685788; Wed, 14 Apr 2021 04:11:25 -0700 (PDT) Received: from [192.168.8.167] ([85.255.235.142]) by smtp.gmail.com with ESMTPSA id b16sm5181575wmb.39.2021.04.14.04.11.24 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 14 Apr 2021 04:11:25 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.4\)) Subject: Re: I-D Action: draft-filsfils-6man-structured-flow-label-00.txt From: Stewart Bryant In-Reply-To: Date: Wed, 14 Apr 2021 12:11:24 +0100 Cc: Stewart Bryant , "Ahmed Abdelsalam (ahabdels)" , Brian E Carpenter , "6man@ietf.org" <6man@ietf.org>, "draft-filsfils-6man-structured-flow-label@ietf.org" Content-Transfer-Encoding: quoted-printable Message-Id: <15A313D3-F6BB-4C2A-9B5B-6CF5F734C9D2@gmail.com> References: <161591339002.5771.1047511172491571607@ietfa.amsl.com> <8BD63262-7C61-4B0C-A988-DA30F4D2AEAF@cisco.com> <29C2D267-BBC9-42D8-AA02-C59415127471@cisco.com> <2BDFBD94-20E5-428E-B28E-57C4697B0E41@cisco.com> To: Ron Bonica X-Mailer: Apple Mail (2.3608.120.23.2.4) Archived-At: X-BeenThere: ipv6@ietf.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "IPv6 Maintenance Working Group \(6man\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Apr 2021 11:11:34 -0000 The normal way to interpret an IETF specification is that unless a = behaviour is proscribed in the specification, it is allowed. It is useful that Ron has noted the existence of routers that ECMP on = those bits in the wild, but the only safe way to have proceeded would = have been to assume that such routers existed since such behaviour was = consistent with a reasonable interpretation of the standard. - Stewart > On 13 Apr 2021, at 19:23, Ron Bonica = wrote: >=20 > Ahmed, >=20 > I know of at least three platforms that use these four bits in flow = hash computation, as described in RFC 6437. >=20 > = Ron >=20 >=20 >=20 > Juniper Business Use Only >=20 > -----Original Message----- > From: Ahmed Abdelsalam (ahabdels) =20 > Sent: Tuesday, April 13, 2021 12:18 PM > To: Ron Bonica ; Brian E Carpenter = ; 6man@ietf.org; = draft-filsfils-6man-structured-flow-label@ietf.org > Subject: Re: I-D Action: = draft-filsfils-6man-structured-flow-label-00.txt >=20 > [External Email. Be cautious of content] >=20 >=20 > Ron, >=20 > As reported in section 4, these 4-bits of Flow Label are not used for = Flow hash computing. Also this makes FLE, used for load-balancing keys = generation, to be byte aligned. >=20 > Cheers, > Ahmed >=20 > =EF=BB=BF-----Original Message----- > From: Ron Bonica > Date: Tuesday, 13 April 2021 at 15:25 > To: ahabdels , Brian E Carpenter = , "6man@ietf.org" <6man@ietf.org>, = "draft-filsfils-6man-structured-flow-label@ietf.org" = > Subject: RE: I-D Action: = draft-filsfils-6man-structured-flow-label-00.txt >=20 > Ahmed, >=20 > I understand that you need to convey four bits of additional = information in basic IPv6 header. Why did you choose to encode this = information in the high order bits of the flow label? Why did you not = choose to encode this information in the low order bits if the IPv6 = destination address? >=20 > = = Ron >=20 >=20 > Juniper Business Use Only >=20 > -----Original Message----- > From: Ahmed Abdelsalam (ahabdels) > Sent: Tuesday, April 13, 2021 4:48 AM > To: Brian E Carpenter ; Ron Bonica = ; 6man@ietf.org; = draft-filsfils-6man-structured-flow-label@ietf.org > Subject: Re: I-D Action: = draft-filsfils-6man-structured-flow-label-00.txt >=20 > [External Email. Be cautious of content] >=20 >=20 > Inline [AA] >=20 > -----Original Message----- > From: Brian E Carpenter > Date: Monday, 12 April 2021 at 22:41 > To: ahabdels , Ron Bonica = , "6man@ietf.org" <6man@ietf.org>, = "draft-filsfils-6man-structured-flow-label@ietf.org" = > Subject: Re: I-D Action: = draft-filsfils-6man-structured-flow-label-00.txt >=20 > On 13-Apr-21 04:01, Ahmed Abdelsalam (ahabdels) wrote: >> Hi Ron, >>=20 >> Thanks for reading the draft. I think we agree on the problem = statement >>=20 >> In our view using a 256-bit HopByHop extension header to encode a = 1-bit flag, is far from efficient. >>=20 >> Also, as you point out, the proposed update in = draft-hinden-6man-hbh-processing (which in my view is going in the right = direction), limits HBH to one single header with one single option. If = we encode the flag in a HbH option, we won=E2=80=99t be able to use HBH = for anything else. >>=20 >> Structured FL can be used for packet marking while HBH can be used in = many other use-cases that require more than simple packet marking. >=20 > But there is no such thing as a structured flow label, because = the standard specifies it as a 20-bit pseudo-random value. As my and = other replies have shown, the proposal is not a backwards compatible = change except possibly in limited domains. =46rom a glance at my inbox, = that has now become the main topic of discussion. >=20 > [AA] Brain, Yes. This draft targets limited domain. We highlighted = this in Recommended Design section and in next revision we are going to = state this at the beginning of the draft. >=20 > Brian >=20 > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > ipv6@ietf.org > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > --------------------------------------------------------------------