+1 (agreeing with Tom and Fred) on retaining this text: > > This document acknowledges that in some cases, packets must be > > fragmented within IP-in-IP tunnels [I-D.ietf-intarea-tunnels]. > > Therefore, this document makes no additional recommendations > > regarding IP-in-IP tunnels.
... for the reasons described below - e.g., "tone" matters in the introduction to this sort of BCP. Thanks, --David > -----Original Message----- > From: Int-area <[email protected]> On Behalf Of Templin (US), Fred > L > Sent: Tuesday, September 3, 2019 5:10 PM > To: Bob Hinden; Tom Herbert > Cc: Joel Halpern; [email protected]; [email protected]; > IESG; [email protected] > Subject: Re: [Int-area] Alissa Cooper's No Objection on draft-ietf-intarea- > frag-fragile-16: (with COMMENT) > > > [EXTERNAL EMAIL] > > Bob, > > > -----Original Message----- > > From: Bob Hinden [mailto:[email protected]] > > Sent: Tuesday, September 03, 2019 1:57 PM > > To: Tom Herbert <[email protected]> > > Cc: Bob Hinden <[email protected]>; Templin (US), Fred L > <[email protected]>; [email protected]; IESG > > <[email protected]>; Joel Halpern <[email protected]>; draft-ietf- > [email protected]; [email protected] > > Subject: Re: [Int-area] Alissa Cooper's No Objection on draft-ietf-intarea- > frag-fragile-16: (with COMMENT) > > > > Tom, > > > > > On Sep 3, 2019, at 1:33 PM, Tom Herbert <[email protected]> > wrote: > > > > > > Bob, > > > > > > I agree with Fred. Note, the very first line of the introduction: > > > > > > "Operational experience [Kent] [Huston] [RFC7872] reveals that IP > > > fragmentation introduces fragility to Internet communication”. > > > > Yes, that text in in the first paragraph of the Introduction > > > > > > This attempts to frame fragmentation as being generally fragile with > > > supporting references. However, there was much discussion on the list > > > about operational experience that demonstrates fragmentation is not > > > fragile. In particular, we know that fragmentation with tunnels is > > > productively deployed and has been for quite some time. So that is the > > > counter argument to the general statement that fragmentation is > > > fragile. With the text about tunneling included in the introduction I > > > believe that was sufficient balance of the arguments, but without the > > > text the reader could be led to believe that fragmentation is fragile > > > for everyone all the time which is simply not true and would be > > > misleading. > > > > Yes, but we are discussing some text from the Introduction that to my read > didn’t say anything useful so I removed it. The substantive > > text about tunneling in in Section 3.5. The Introduction, is just the > introduction. The text was: > > > > This document acknowledges that in some cases, packets must be > > fragmented within IP-in-IP tunnels [I-D.ietf-intarea-tunnels]. > > Therefore, this document makes no additional recommendations > > regarding IP-in-IP tunnels. > > Yes - good text that should be retained. > > > Why is that more useful than what is in 3.5? If it’s not making a > recommendation, why call this out in the introduction. There are lot of > > other things it doesn’t make recommendations about that aren’t in the > Introduction either. > > Because it sets a more appropriate tone and lets the reader know from the > onset that > fragmentation and encapsulation go hand in hand. And tunnel fragmentation > avoids the > issues raised by others in this thread. > > Thanks - Fred > > > Bob > > > > > > > > Speaking of balance, the introduction also mentions that: > > > > > > "this document recommends that upper-layer protocols address the > > > problem of fragmentation at their layer" > > > > > > But the "problem" of fragmentation is in intermediate devices that > > > don't properly handle it as the draft highlights. So it seems like > > > part of addressing the problem should also be to fix the problem! That > > > is implementations should be fixed to deal with fragmentation. IMO, > > > this should be another high level recommendation that is mentioned in > > > the introduction. > > > > I am serving as document editor. This to my understanding has been > through w.g. last call and now IESG review. > > > > > > Tom > > > > > > > > > > > > Tom > > > > > > > > > > > > > > > > > > On Tue, Sep 3, 2019 at 1:01 PM Bob Hinden <[email protected]> > wrote: > > >> > > >> Fred, > > >> > > >>> On Sep 3, 2019, at 12:45 PM, Templin (US), Fred L > <[email protected]> wrote: > > >>> > > >>> Bob, > > >>> > > >>>> -----Original Message----- > > >>>> From: Bob Hinden [mailto:[email protected]] > > >>>> Sent: Tuesday, September 03, 2019 9:10 AM > > >>>> To: Templin (US), Fred L <[email protected]> > > >>>> Cc: Bob Hinden <[email protected]>; Joe Touch > <[email protected]>; Alissa Cooper <[email protected]>; Joel > > Halpern > > >>>> <[email protected]>; draft-ietf-intarea-frag- > [email protected]; [email protected]; IESG <[email protected]>; intarea- > > >>>> [email protected] > > >>>> Subject: Re: [Int-area] Alissa Cooper's No Objection on draft-ietf- > intarea-frag-fragile-16: (with COMMENT) > > >>>> > > >>>> Fred, > > >>>> > > >>>>> On Sep 3, 2019, at 7:33 AM, Templin (US), Fred L > <[email protected]> wrote: > > >>>>> > > >>>>> Why was this section taken out: > > >>>>> > > >>>>>> 1.1. IP-in-IP Tunnels > > >>>>>> > > >>>>>> This document acknowledges that in some cases, packets must be > > >>>>>> fragmented within IP-in-IP tunnels [I-D.ietf-intarea-tunnels]. > > >>>>>> Therefore, this document makes no additional recommendations > > >>>>>> regarding IP-in-IP tunnels. > > >>>> > > >>>> This text in the Introduction was removed because, as noted in > Warren Kumari > > >>>> Comment (2019-08-07 for -15), this didn’t need to be in the > introduction, and it didn’t say very much that isn’t described later in > > the > > >>>> document. > > >>>> > > >>>> The normative text in Section 5.3. "Packet-in-Packet Encapsulations” > is unchanged. I think Section 5.3 covers the topic. It > > includes the > > >>>> reference to [I-D.ietf-intarea-tunnels]. > > >>> > > >>> While I agree that both passages supply a working vector to 'intarea- > tunnels', > > >>> the two strike very different tones. The former gives a balanced > citation, while > > >>> the latter calls it a "corner case" - twice! > > >>> > > >>> Whether we like it or not, fragmentation and encapsulation will > continue to > > >>> be associated with each other no matter what gets documented here. > So, > > >>> a respectful handoff to 'intarea-tunnels' would be appreciated. > > >> > > >> You are talking about text in the Introduction of the document. > > >> > > >> The important substance relating to tunnels is in Section 5.3. The text > is: > > >> > > >> 5.3. Packet-in-Packet Encapsulations > > >> > > >> In this document, packet-in-packet encapsulations include IP-in-IP > > >> [RFC2003], Generic Routing Encapsulation (GRE) [RFC2784], GRE-in- > UDP > > >> [RFC8086] and Generic Packet Tunneling in IPv6 [RFC2473]. [RFC4459] > > >> describes fragmentation issues associated with all of the above- > > >> mentioned encapsulations. > > >> > > >> The fragmentation strategy described for GRE in [RFC7588] has been > > >> deployed for all of the above-mentioned encapsulations. This > > >> strategy does not rely on IP fragmentation except in one corner case. > > >> (see Section 3.3.2.2 of RFC 7588 and Section 7.1 of RFC 2473). > > >> Section 3.3 of [RFC7676] further describes this corner case. > > >> > > >> See [I-D.ietf-intarea-tunnels] for further discussion. > > >> > > >> Seems fine to me, in tone and substance. > > >> > > >> Bob > > >> > > >> > > >>> > > >>> Fred > > >>> > > >>>> Bob > > >>>> > > >>>> > > >>>>> > > >>>>> Tunnels always inflate the size of packets to the point that they may > exceed > > >>>>> the path MTU even if the original packet is no larger than the path > MTU. And, > > >>>>> for IPv6 the only guarantee is 1280. Therefore, in order to robustly > support > > >>>>> the minimum IPv6 MTU tunnels MUST employ fragmentation. > > >>>>> > > >>>>> Please put this section of text back in the document where it > belongs. > > >>>>> > > >>>>> Thanks - Fred > > >>>>> > > >>>>>> -----Original Message----- > > >>>>>> From: Int-area [mailto:[email protected]] On Behalf Of > Joe Touch > > >>>>>> Sent: Tuesday, September 03, 2019 7:06 AM > > >>>>>> To: Alissa Cooper <[email protected]> > > >>>>>> Cc: Joel Halpern <[email protected]>; draft-ietf-intarea- > [email protected]; [email protected]; The IESG > > >>>> <[email protected]>; > > >>>>>> [email protected] > > >>>>>> Subject: Re: [Int-area] Alissa Cooper's No Objection on draft-ietf- > intarea-frag-fragile-16: (with COMMENT) > > >>>>>> > > >>>>>> Hi, all, > > >>>>>> > > >>>>>> So let me see if I understand: > > >>>>>> > > >>>>>> Alissa issues a comment. > > >>>>>> > > >>>>>> We discuss this on the list and come to a rare consensus on a way > forward. > > >>>>>> > > >>>>>> The new draft is issued that: > > >>>>>> > > >>>>>> a) ignores the list consensus > > >>>>>> b) removes a paragraph not under the DISCUSS (1.1) > > >>>>>> c) now refers to vague “other documents” without citation > > >>>>>> d) most importantly: > > >>>>>> > > >>>>>> REMOVES a key recommendation that we MAY use frag where it > works > > >>>>>> > > >>>>>> Asserts the false claim that IP fragmentation “will fail” in the > Internet, > > >>>>>> despite citing evidence that the *majority of the time* it does > work > > >>>>>> e.g., for IPv6, sec 3.9 > > >>>>>> > > >>>>>> What happened? Why is a change this substantial not reflecting > the *list consensus*? > > >>>>>> > > >>>>>> Joe > > >>>>>> > > >>>>>>> On Sep 3, 2019, at 5:59 AM, Alissa Cooper via Datatracker > <[email protected]> wrote: > > >>>>>>> > > >>>>>>> Alissa Cooper has entered the following ballot position for > > >>>>>>> draft-ietf-intarea-frag-fragile-16: No Objection > > >>>>>>> > > >>>>>>> When responding, please keep the subject line intact and reply to > all > > >>>>>>> email addresses included in the To and CC lines. (Feel free to cut > this > > >>>>>>> introductory paragraph, however.) > > >>>>>>> > > >>>>>>> > > >>>>>>> Please refer to https://www.ietf.org/iesg/statement/discuss- > criteria.html > > >>>>>>> for more information about IESG DISCUSS and COMMENT > positions. > > >>>>>>> > > >>>>>>> > > >>>>>>> The document, along with other ballot positions, can be found > here: > > >>>>>>> https://datatracker.ietf.org/doc/draft-ietf-intarea-frag-fragile/ > > >>>>>>> > > >>>>>>> > > >>>>>>> > > >>>>>>> ---------------------------------------------------------------------- > > >>>>>>> COMMENT: > > >>>>>>> ---------------------------------------------------------------------- > > >>>>>>> > > >>>>>>> Thanks for addressing my DISCUSS. > > >>>>>>> > > >>>>>>> > > >>>>>>> _______________________________________________ > > >>>>>>> Int-area mailing list > > >>>>>>> [email protected] > > >>>>>>> https://www.ietf.org/mailman/listinfo/int-area > > >>>>>> > > >>>>>> _______________________________________________ > > >>>>>> Int-area mailing list > > >>>>>> [email protected] > > >>>>>> https://www.ietf.org/mailman/listinfo/int-area > > >>> > > >> > > >> _______________________________________________ > > >> Int-area mailing list > > >> [email protected] > > >> https://www.ietf.org/mailman/listinfo/int-area > > _______________________________________________ > Int-area mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/int-area _______________________________________________ Int-area mailing list [email protected] https://www.ietf.org/mailman/listinfo/int-area
