Joe, All things are fragile. That's one of life's realities.
But some things are more fragile than others. Ron Juniper Business Use Only -----Original Message----- From: Joe Touch <to...@strayalpha.com> Sent: Thursday, August 15, 2019 10:21 AM To: Ron Bonica <rbonica=40juniper....@dmarc.ietf.org> Cc: Brian E Carpenter <brian.e.carpen...@gmail.com>; Alissa Cooper <ali...@cooperw.in>; Tom Herbert <t...@herbertland.com>; Joel Halpern <joel.halp...@ericsson.com>; draft-ietf-intarea-frag-frag...@ietf.org; int-area <int-area@ietf.org>; IESG <i...@ietf.org>; intarea-chairs <intarea-cha...@ietf.org> Subject: Re: [Int-area] Alissa Cooper's Discuss on draft-ietf-intarea-frag-fragile-15: (with DISCUSS and COMMENT) Well, there’s the tautology that “it worked when it worked”. Given that’s basically the rule that defines *everything* in the Internet, it’s baffling we need to say it again here, but if we did, we could simply state: “The Internet is a best-effort system and lacks a formal validation or conformance mechanism. Like any other protocol feature, IP fragmentation is useful only when it actually works - both by successfully traversing routers and other in-network devices and when it is correctly supported by endpoints. As a consequence, like any other protocol feature, IP fragmentation MAY be used by new protocols that validate its successful traversal and provide an alternate as a backup.” (and yes, if we’re going to try to imply that frag is limited, it really should be clear that this is *no different than any other protocol feature* in the Internet) Joe > On Aug 15, 2019, at 6:59 AM, Ron Bonica > <rbonica=40juniper....@dmarc.ietf.org> wrote: > > Folks, > > Has anyone proposed text that: > > a) satisfies Alissa's request > b) satisfies the WG > > If not, do we believe that such text could possibly exist? > > Ron > > > > > Juniper Business Use Only > > -----Original Message----- > From: Brian E Carpenter <brian.e.carpen...@gmail.com> > Sent: Tuesday, August 6, 2019 8:55 PM > To: Alissa Cooper <ali...@cooperw.in>; Tom Herbert > <t...@herbertland.com> > Cc: Joel Halpern <joel.halp...@ericsson.com>; > draft-ietf-intarea-frag-frag...@ietf.org; int-area > <int-area@ietf.org>; IESG <i...@ietf.org>; intarea-chairs > <intarea-cha...@ietf.org> > Subject: Re: [Int-area] Alissa Cooper's Discuss on > draft-ietf-intarea-frag-fragile-15: (with DISCUSS and COMMENT) > > On 07-Aug-19 12:11, Alissa Cooper wrote: >> Hi Tom, >> >>> On Aug 6, 2019, at 5:41 PM, Tom Herbert <t...@herbertland.com> wrote: >>> >>> On Tue, Aug 6, 2019 at 1:30 PM Alissa Cooper via Datatracker >>> <nore...@ietf.org> wrote: >>>> >>>> Alissa Cooper has entered the following ballot position for >>>> draft-ietf-intarea-frag-fragile-15: Discuss >>>> >>>> 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://urldefense.proofpoint.com/v2/url?u=https-3A__www.ietf.org_i >>>> e >>>> sg_statement_discuss-2Dcriteria.html&d=DwIFaQ&c=HAkYuh63rsuhr6Scbfh >>>> 0 >>>> UjBXeMK-ndb3voDTXcWzoCI&r=Fch9FQ82sir-BoLx84hKuKwl-AWF2EfpHcAwrDThK >>>> P >>>> 8&m=IUZsPOprgYi_5nBSPGeqNCLb8LwDMKCxRNeEBfcUZ5c&s=c7tAk-Lfr6pcQSMn1 >>>> x 1tdfjkQsL8F_NryIiq3caZ26k&e= for more information about IESG >>>> DISCUSS and COMMENT positions. >>>> >>>> >>>> The document, along with other ballot positions, can be found here: >>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__datatracker.ie >>>> t >>>> f.org_doc_draft-2Dietf-2Dintarea-2Dfrag-2Dfragile_&d=DwIFaQ&c=HAkYu >>>> h >>>> 63rsuhr6Scbfh0UjBXeMK-ndb3voDTXcWzoCI&r=Fch9FQ82sir-BoLx84hKuKwl-AW >>>> F >>>> 2EfpHcAwrDThKP8&m=IUZsPOprgYi_5nBSPGeqNCLb8LwDMKCxRNeEBfcUZ5c&s=lb6 >>>> u 0SVhJIFnTV7TdqeLiDBfadRxJkAxNEDqOvFqhyQ&e= >>>> >>>> >>>> >>>> ------------------------------------------------------------------- >>>> - >>>> -- >>>> DISCUSS: >>>> ------------------------------------------------------------------- >>>> - >>>> -- >>>> >>>> Thanks for writing this document. >>>> >>>> Section 6.1 says: >>>> >>>> "Developers MAY develop new protocols or applications that rely on >>>> IP fragmentation if the protocol or application is to be run only >>>> in environments where IP fragmentation is known to be supported." >>>> >>>> I'm wondering if there should be a bit more nuance here to make the >>>> recommendation clearer. Do we think there is a case where an >>>> application protocol developed in the IETF will be known to only >>>> run in environments where fragmentation is supported? If we don't >>>> think developing such a protocol would be in scope for the IETF, >>>> then I'm wondering if that case should be called out explicitly with a >>>> stronger normative requirement. >>>> >>> Alissa, >>> >>> Are you distinguishing between protocol development and application >>> development? >> >> I’m specifically wondering about application protocols (as distinct from >> other protocols) developed in the IETF (as distinct from developed >> elsewhere). Sometimes we use BCPs to guide future work in the IETF >> specifically, and it seemed to me that in that specific slice — >> IETF-developed application protocols — we may be able to make a stronger >> recommendation since we can’t be sure of the environment in which any given >> application protocol would be deployed (I think, but would be open to >> arguments otherwise). > > fwiw, I agree with what I think Alissa is saying. Unless we actually > *implement* a mechanism to define and support limited domains > (draft-carpenter-limited-domains) protocol designers cannot safely make > assumptions such as "fragmentation works". > > Maybe this paragraph needs to be more of a health warning than a somewhat > dubious RFC2119 statement. At least, "should not ... unless" might be a > better formulation than "MAY ... if". > > Brian > _______________________________________________ > Int-area mailing list > Int-area@ietf.org > https://urldefense.proofpoint.com/v2/url?u=https-3A__www.ietf.org_mail > man_listinfo_int-2Darea&d=DwIFaQ&c=HAkYuh63rsuhr6Scbfh0UjBXeMK-ndb3voDTXcWzoCI&r=Fch9FQ82sir-BoLx84hKuKwl-AWF2EfpHcAwrDThKP8&m=eXUulHqfbw3R3myfDaucAqDwAy7RLoWhE407vuTA0Mo&s=VMkjr7T57NEpDAKpUz6DP8lDN3K2Q69yenoxF6WUtDU&e= _______________________________________________ Int-area mailing list Int-area@ietf.org https://www.ietf.org/mailman/listinfo/int-area