Re: [IPv6] Progress of comments resolution on draft-ietf-6man-enhanced-vpn-vtn-id
Gyan Mishra <hayabusagsm@gmail.com> Tue, 09 January 2024 08:16 UTC
Return-Path: <hayabusagsm@gmail.com>
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 D669BC1CAF27; Tue, 9 Jan 2024 00:16:23 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.094
X-Spam-Level:
X-Spam-Status: No, score=-2.094 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, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_REMOTE_IMAGE=0.01, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_BLOCKED=0.001, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xUjuKqTr_Kdv; Tue, 9 Jan 2024 00:16:19 -0800 (PST)
Received: from mail-ot1-x32d.google.com (mail-ot1-x32d.google.com [IPv6:2607:f8b0:4864:20::32d]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 1BCF2C14F5E8; Tue, 9 Jan 2024 00:16:07 -0800 (PST)
Received: by mail-ot1-x32d.google.com with SMTP id 46e09a7af769-6dddb927d02so633197a34.2; Tue, 09 Jan 2024 00:16:07 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1704788166; x=1705392966; darn=ietf.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=Vzjr1/jx2sRmUcXA2oBUTHgfM7r8N+Mac5kfvNKF6Yk=; b=l2P4wwpTyZUXHUTyudIBXO5vo7bAXDvBgt1Inasgypsm/fw953xzYPqoutCksHKClb T8JA8fO05sy24oGexoItBLQYlykuqXw0VqPNHtjXrS3n2TqGoFJ8SdrOVnSBQoRRsxcd wzq6WoXnG0oGpjdcjxu5y40uzuaWWzAV/I7GfDqF/wxI/RQSoaZs4coFneT5iLt8LDVF oFvYryeeWMcEvXBE0N4z36X8CeRLmtpBMWx6ARG8YA63vldZ6+70LF66Erj3NetsiVlS Lxb1ynBoyEn5HcDhsoMqE8Oz/FyOdGb3nBAWmLjI2rQcDSPUD31r78hZa7iJfF7us4GU 6amA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1704788166; x=1705392966; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Vzjr1/jx2sRmUcXA2oBUTHgfM7r8N+Mac5kfvNKF6Yk=; b=cSQkK508zf+9NONmDA0IPfDq/+mwRHmg/BW5psIjrKyDqrdRE4Lu1QuKcxv/wjihj0 szjwQhNpm+eqdyriL45jqb7R80X3GBBHmWx8Io0yft9oFpZPcBEhtff6VnS8spP4EUSK yeFJBOIuwSjFTc9f3BsTq0gkgvfcfwdmV9QCNHCzoxJkpGas/loR1agsGkrdCXwIDvhI Ax9zZAs9hyy82DLpAXgoKMiQ1Ni9T2ipUoEWkWXEe/+ZVKcQJrWLjgCnuKqnIINfNH30 KJMevRunDHed7WpOGKHNoW+LAloWmjAdz4vUiy4vQVUdcH4JY281wkg6z5UoxSbMa53B CwVw==
X-Gm-Message-State: AOJu0YxzSSgelpxlvmCi4hcd7IrYebgnSin5t9YKfabWQhFMiT1T8CMI m+Nv6sOrEOzeGT/At3XlFE1iT4sdNYIJqI6hTDOw4tSAG3U=
X-Google-Smtp-Source: AGHT+IEa1Z1EEVUskib1/7jUYClzAiLjce6xaRarAe0n8ebXlLLeikEO1XaPWPG5rr1W3b3vImakMPGoMb84QN7m+Bk=
X-Received: by 2002:a05:6358:998a:b0:175:4fc2:1ab4 with SMTP id j10-20020a056358998a00b001754fc21ab4mr6334162rwb.45.1704788166125; Tue, 09 Jan 2024 00:16:06 -0800 (PST)
MIME-Version: 1.0
References: <165d35ecaaa44a3daff0783cd161eb12@huawei.com> <014c01da2cde$f6e31510$e4a93f30$@olddog.co.uk> <2fcc89b28bc64c7cb5cf2abf20319006@huawei.com> <021e01da2d1d$2efc2930$8cf47b90$@olddog.co.uk> <DU2PR02MB1016002CC68F1D799A4562D9D888CA@DU2PR02MB10160.eurprd02.prod.outlook.com> <fc34b0f89c3f4af2b4fb5c5dc5d9f7bd@huawei.com> <05a901da3503$3d7a9a30$b86fce90$@olddog.co.uk> <CABNhwV1bh6zSwH=hCame5SJroKUvu-q0GwkZrGaMwVkkTptSHw@mail.gmail.com> <764df175d9f74bc4b5ba99bee7271295@huawei.com>
In-Reply-To: <764df175d9f74bc4b5ba99bee7271295@huawei.com>
From: Gyan Mishra <hayabusagsm@gmail.com>
Date: Tue, 09 Jan 2024 03:15:30 -0500
Message-ID: <CABNhwV3JB-AHHCVW22K-fy3ZdchQZPBwp5agN8hKrj=dk1Rx0Q@mail.gmail.com>
To: "Dongjie (Jimmy)" <jie.dong@huawei.com>
Cc: "adrian@olddog.co.uk" <adrian@olddog.co.uk>, 6man <ipv6@ietf.org>, "draft-ietf-6man-enhanced-vpn-vtn-id@ietf.org" <draft-ietf-6man-enhanced-vpn-vtn-id@ietf.org>, "mohamed.boucadair@orange.com" <mohamed.boucadair@orange.com>
Content-Type: multipart/alternative; boundary="0000000000000f29fc060e7eed29"
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/mD73i1lqafaJAE2_CNn41jLf3l8>
Subject: Re: [IPv6] Progress of comments resolution on draft-ietf-6man-enhanced-vpn-vtn-id
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ipv6/>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 09 Jan 2024 08:16:23 -0000
Hi Jie Welcome. I will review the draft some more and try to think of some other possible use cases for the S bit. Thanks Gyan On Tue, Jan 9, 2024 at 2:40 AM Dongjie (Jimmy) <jie.dong@huawei.com> wrote: > Hi Gyan, > > Thanks for sharing your opinion on the S flag. It is good to know you > agree with keeping the S flag in this document. > > Our plan is to update the draft with some text to describe the usage of > the S bit, and we are still open to opinions and suggestions. > > Best regards, > Jie > > > -----Original Message----- > > From: Gyan Mishra [mailto:hayabusagsm@gmail.com] > > Sent: Saturday, January 6, 2024 4:10 PM > > To: adrian@olddog.co.uk > > Cc: 6man <ipv6@ietf.org>; Dongjie (Jimmy) <jie.dong@huawei.com>; > > draft-ietf-6man-enhanced-vpn-vtn-id@ietf.org; > > mohamed.boucadair@orange.com > > Subject: Re: [IPv6] Progress of comments resolution on > > draft-ietf-6man-enhanced-vpn-vtn-id > > > > All, > > > > I agree with Jie & Adrian that the S flag should be kept in the same > document > > and not split out. > > > > As the S flag is part of the 8 bit flag field of the NRP ID and is > intrinsic to the > > specification for carrying the NRP ID in an IPv6 extension header, I > believe the > > S flag should be kept in the draft. > > > > As pointed out by Adrian & Jie that the S flag provides more granularity > > per-NRP ID per packet, per flow characteristic then is possible using a > > configuration option for the case where the NRP ID does not match and the > > drop of forward behavior. > > > > Jie mentioned the BFD control packets use case however this could apply > to > > any OAM telemetry use case where strict match is required. There as well > > maybe other data path telemetry control packets use cases such as maybe > > used by SR Policy SR PM STAMP/TWAMP packets that may need this S flag > > requirement for steering per NRP ID, per packet or per flow into a Flex > Algo > > NRP ID sub topology network slice. > > > > The S flag could also could be used with SR path tracing telemetry probe > > packets per draft below: > > > > https://datatracker.ietf.org/doc/draft-filsfils-spring-path-tracing/ > > > > > > Kind Regards > > > > <http://www.verizon.com/> > > > > *Gyan Mishra* > > > > *Network Solutions A**rchitect * > > > > *Email gyan.s.mishra@verizon.com <gyan.s.mishra@verizon.com>* > > > > > > > > *M 301 502-1347* > > > > > > > > On Fri, Dec 22, 2023 at 1:18 PM Adrian Farrel <adrian@olddog.co.uk> > wrote: > > > > > Well, I'm going to pile in once more (it *is* Christmas) and then sit > > > back to see whether there are other opinions... > > > > > > > > > > > > - As Ketan observed (a little late ;-) the proposed S flag comes > from > > > the NRP ID extension header, so there is no shortage of flags. > > > > > > > > > > > > - Yes, Med is right, this function could be configured at each node. > > > Indeed, most things can be configured at nodes, but does that mean > > we > > > discard the IGPs? :-) > > > > > > > > > > > > - The S flag provides greater granularity than can be achieved with > > > configuration. If you configure "discard or best effort" you have > some > > > choices: > > > > > > > > > > > > - Configure the default behaviour for "I don't have resources for > this > > > NRP ID". That is relatively simple, but it is "one size fits > all." > > > - Configure the behaviour for each NRP ID that might be seen and > > > for which resources aren’t reserved. That feels like a nightmare > for > > > configuration. > > > - Set the requested behaviour in the packet (as the S flag) which > > > allows different behaviours for different NRP IDs without the > > overhead of > > > configuration on nodes that are unlikely to see packets for an > NRP > > ID for > > > which they don’t have reserved resources. > > > > > > > > > > > > - In fact, the S flag provides even greater granularity because it > can > > > be set per packet meaning that some packets within the NRP can take > > best > > > effort, while others can be dropped. This, I think, recognises that > an > > NRP > > > carries multiple flows for different purposes (easy example is that > > > different network slices might need different treatments). > > > > > > > > > > > > And (again, in case any one is still worried) the NRP ID in the packet > > > is not used to make any routing or forwarding decisions. It simply > > > indicates which resources (bandwidth, queues, …) are used by the > packet. > > > > > > > > > > > > So, I **do** see that the S flag could be moved to another document. > > > However, I think that would be jut making work for everyone. I also > > > think it would be odd to define the base extension header with a flags > > > field that has no flags defined – if I were an external reviewer of > > > that, I would say that the field should be marked “Reserved” not > > > “Flags”, meaning that the document that defined the S flag would also > > > have to Update the base spec to define the Flags field. > > > > > > > > > > > > Cheers, > > > > > > Adrian > > > > > > > > > > > > -----Original Message----- > > > From: Dongjie (Jimmy) <jie.dong@huawei.com> > > > Sent: 18 December 2023 15:47 > > > To: mohamed.boucadair@orange.com; adrian@olddog.co.uk > > > Cc: '6man' <ipv6@ietf.org>; > > > draft-ietf-6man-enhanced-vpn-vtn-id@ietf.org > > > Subject: RE: [IPv6] Progress of comments resolution on > > > draft-ietf-6man-enhanced-vpn-vtn-id > > > > > > > > > > > > Hi Med and Adrian, > > > > > > > > > > > > Thanks for the discussion. Here I'd like to give some further > > > explanation about the usage of the S bit and why it is considered > useful. > > > > > > > > > > > > In normal IPv6 packet forwarding, the next-hop and outgoing interface > > > are determined based on longest matching of the destination IPv6 > address. > > > Packets with unmatched destination address are always dropped. > > > > > > > > > > > > After the introduction of the VTN (or NRP, will use VTN just in this > > > mail) option, the next-hop and outgoing interface are still determined > > > based on the destination address, this is unchanged. > > > > > > > > > > > > Then for packets whose next-hop and outgoing interface are determined, > > > the VTN ID in the packet is used to match with the sets of local > > > resources allocated to VTNs on the outgoing interface. There are two > > possible results: > > > > > > > > > > > > 1) The VTN ID in the packet matches with the same VTN ID which is > > > configured on the outgoing interface with a set of network resources, > > > then the packet is forwarded using that set of resources. > > > > > > > > > > > > 2) The VTN ID in the packet does not match with any VTN ID > > > configured on the outgoing interface. How should the node behave in > > > this case? There are two options: 1) forward the packet with best > effort. 2) > > discard the packet. > > > > > > > > > > > > The S flag is used to tell the node how to forward the packet when the > > > VTN-ID is not configured on the outgoing interface. > > > > > > > > > > > > With the above, I hope the functionality of the S flag is clear. > > > > > > > > > > > > Then the possible question is can this be achieved by configuration? > > > > > > > > > > > > The answer is it can, but possibly with a relatively higher cost. Note > > > this is to control the behavior for NRPs which are not provisioned on > > > the node's outgoing interface. Usually devices do not provide control > > > configuration for elements which are not enabled. Even if such > > > configuration is supported, as the behavior can be different per NRP, > > > this requires lots of configuration for NRPs which are not enabled. > > > Then we also need to consider the case where the behavior may be > > > different for different flows under the same NRP... > > > > > > > > > > > > One analogy (not quite the same) to the S flag is the bits in IPv6 > > > extension header options which are used to control the forwarding > > > behavior when the option cannot be parsed by some node. That may also > > > be achieved via configuration on the nodes, while it turns out a > > > better choice is to use flags to indicate the behavior for unrecognized > > entities. > > > > > > > > > > > > With the above analysis, hope you also agree that the S flag is a more > > > efficient approach for the required functionality. > > > > > > > > > > > > Best regards, > > > > > > Jie > > > > > > > > > > > > > -----Original Message----- > > > > > > > From: mohamed.boucadair@orange.com > > <mohamed.boucadair@orange.com> > > > > > > > Sent: Thursday, December 14, 2023 8:23 PM > > > > > > > To: adrian@olddog.co.uk; Dongjie (Jimmy) <jie.dong@huawei.com> > > > > > > > Cc: '6man' <ipv6@ietf.org>; > > > > draft-ietf-6man-enhanced-vpn-vtn-id@ietf.org > > > > > > > Subject: RE: [IPv6] Progress of comments resolution on > > > > > > > draft-ietf-6man-enhanced-vpn-vtn-id > > > > > > > > > > > > > > Hi Adrian, > > > > > > > > > > > > > > > If the reason for splitting was technical or made for a radical > > > > > > > > improvement in readability, I might buy it. But I think it is > > > > > purely a > > > > > > > > documentation issue. > > > > > > > > > > > > > > It isn't. > > > > > > > > > > > > > > The issue is that the use of the S bit is not justified, including > > > > with > > > the case you > > > > > > > mentioned below. This scan be handled by a local config parameter. I > > > fail to see > > > > > > > valid arguments so far why a per-NRP per-packet behavior will needed > > > > to > > > > > > > process a packet. > > > > > > > > > > > > > > Cheers, > > > > > > > Med > > > > > > > > > > > > > > > -----Message d'origine----- > > > > > > > > De : ipv6 <ipv6-bounces@ietf.org> De la part de Adrian Farrel > Envoyé : > > > > > > > > mardi 12 décembre 2023 18:04 À : 'Dongjie (Jimmy)' > > > > > > > > <jie.dong@huawei.com> Cc : '6man' <ipv6@ietf.org>; > > > > > > > > draft-ietf-6man-enhanced-vpn-vtn- id@ietf.org Objet : Re: [IPv6] > > > > > > > > Progress of comments resolution on draft-ietf- > > > > > > > > 6man-enhanced-vpn-vtn-id > > > > > > > > > > > > > > > > Hi Jie, > > > > > > > > > > > > > > > > I rather expected some more comments on this, and I sat back to > > > > > watch > > > > > > > > them, but then it went quiet and I forgot. > > > > > > > > > > > > > > > > So, "better late than never". > > > > > > > > > > > > > > > > As an aside, I wonder whether you should follow the advice given > > > > > by > > > > > > > > TEAS in its work on draft-ietf-teas-enhanced-vpn, and feeding into > > > > > IDR > > > > > > > > on draft-dong-idr-sr-policy-nrp. That is, generalise the VTN use > > > > > case > > > > > > > > to NRP. I don't think this makes any technical change to the > > > > > document, > > > > > > > > but makes the applicability wider (more > > > > > > > > generic) in step with what TEAS is doing. This seems to in keeping > > > > > > > > with the suggestions in your Section 5. But it would require some > > > > > > > > editorial work. > > > > > > > > > > > > > > > > I am not enthusiastic about splitting out multiple documents. It > > > > > just > > > > > > > > makes more work. > > > > > > > > > > > > > > > > While I understand that the authors and Med thought this might be > > > > > a > > > > > > > > compromise, I doubt that the authors really want to do this (that > > > > > is, > > > > > > > > make more work for themselves) and since no one spoke up on the > > > > > list, > > > > > > > > I wonder whether it the (perfectly valid) preference of only one > > > > > > > > person. > > > > > > > > > > > > > > > > If the reason for splitting was technical or made for a radical > > > > > > > > improvement in readability, I might buy it. But I think it is > > > > > purely a > > > > > > > > documentation issue. > > > > > > > > > > > > > > > > It is worth noting that if the document was split then, without > > > > > the S > > > > > > > > flag, the whole flags field would be unused in the remaining > > > > > document > -- <http://www.verizon.com/> *Gyan Mishra* *Network Solutions A**rchitect * *Email gyan.s.mishra@verizon.com <gyan.s.mishra@verizon.com>* *M 301 502-1347*
- [IPv6] Progress of comments resolution on draft-i… Dongjie (Jimmy)
- Re: [IPv6] Progress of comments resolution on dra… Adrian Farrel
- Re: [IPv6] Progress of comments resolution on dra… Chongfeng Xie
- Re: [IPv6] Progress of comments resolution on dra… Dongjie (Jimmy)
- Re: [IPv6] Progress of comments resolution on dra… mohamed.boucadair
- Re: [IPv6] Progress of comments resolution on dra… Dongjie (Jimmy)
- Re: [IPv6] Progress of comments resolution on dra… Ketan Talaulikar
- Re: [IPv6] Progress of comments resolution on dra… Ketan Talaulikar
- Re: [IPv6] Progress of comments resolution on dra… Dongjie (Jimmy)
- Re: [IPv6] Progress of comments resolution on dra… mohamed.boucadair
- Re: [IPv6] Progress of comments resolution on dra… Dongjie (Jimmy)
- Re: [IPv6] Progress of comments resolution on dra… Adrian Farrel
- Re: [IPv6] Progress of comments resolution on dra… Gyan Mishra
- Re: [IPv6] Progress of comments resolution on dra… Dongjie (Jimmy)
- Re: [IPv6] Progress of comments resolution on dra… Gyan Mishra
- Re: [IPv6] Progress of comments resolution on dra… mohamed.boucadair
- Re: [IPv6] Progress of comments resolution on dra… Dongjie (Jimmy)
- Re: [IPv6] Progress of comments resolution on dra… mohamed.boucadair
- Re: [IPv6] Progress of comments resolution on dra… Dongjie (Jimmy)