Paul, > > So, (as WG chair for this paragraph only), thank you for your input, but > > this is a > single draft for very good reasons. > > </WG chair hat> > > Thanks for the explanation. The thing about genart reviews is that the > reviewer doesn't have the context that the authors do, and maybe not the > context that likely readers will have. I certainly won't second guess > you on that.
And double-checking this sort of thing is one of the purposes of Gen-ART reviews (said as a long-time former Gen-ART reviewer), so thanks for bringing this topic up - if nothing else, we now have this concern and response documented in email archives for IESG review of this draft ;-). Thanks, --David > -----Original Message----- > From: Paul Kyzivat [mailto:pkyzi...@alum.mit.edu] > Sent: Tuesday, May 31, 2016 10:09 AM > To: Black, David; draft-ietf-tsvwg-rfc5405bis....@ietf.org > Cc: General Area Review Team > Subject: Re: Gen-ART Last Call review of draft-ietf-tsvwg-rfc5405bis > > On 5/31/16 9:52 AM, Black, David wrote: > > Paul, > > > > Many thanks for the review. > > > >> (1) Major? - Scope and Audience > > > >> Beyond that it delves into a seeming random assortment of additional > >> specialized uses of UDP. These may be of interest to some, but I suspect > >> many won't find these things useful. And the topics covered seem to be > >> simply what came to mind rather than being in some way exhaustive. > > > > Actually, the selection algorithm is dominated by what's come up in > > practice and > merits advice - Section 3.6 on Limited Applicability and Controlled > Environments is > an excellent example. > > > >> After diffing this document against RFC5405 I see that it really is an > >> incremental change that leaves the scope largely unchanged except for > >> the addition of multicast. So perhaps I am too late to question the > >> scope of the document. But since this *is* a bis, it might be worth > >> considering whether the scope could be focused by splitting some of the > >> material off into a different document(s). > > > > <WG chair hat> > > Well, I think you're in the "rough" on "rough consensus" here - as this > > draft is > targeted at designers and developers, there is strong WG "rough consensus" to > put everything in one place. To this end, multiple drafts were combined by > the > WG (e.g., the multicast requirements used to be in a separate draft). > > > > So, (as WG chair for this paragraph only), thank you for your input, but > > this is a > single draft for very good reasons. > > </WG chair hat> > > Thanks for the explanation. The thing about genart reviews is that the > reviewer doesn't have the context that the authors do, and maybe not the > context that likely readers will have. I certainly won't second guess > you on that. > > >> (2) MINOR? - use of SHOULD > >> > >> I was struck by how much SHOULD is used in this document, and how > >> infrequently MUST is used. And while possible justifications for > >> violating SHOULD are sometimes provided, they often are not. In my > >> experience there has been a growing awareness that such vagueness is > >> problematic, because many implementers take it as free license to treat > >> SHOULD as MAY, and just not do it. > > > > I concur - an author scan for use of "SHOULD" would make sense to do a > > couple > of things: > > > > - Make sure the rationale for the strong recommendation is explained. > > - Consider upgrading to "MUST". Otherwise, ensure that potential > consequences of not following the "SHOULD" are described. > > > > I prefer describing possible consequences to suggesting justifications for > violation, as the latter (IMHO) encourages the (undesirable) behavior of > designers and implementers "treat[ing] SHOULD as MAY," and the former is a > better match to RFC 2119's definition of "SHOULD." > > IMO this is still an unresolved topic in the IETF. Until (and unless) it > is resolved, groups will treat as they see best. > > As best I can understand, there is no difference between "SHOULD unless > ..." and "MUST unless ...". So perhaps the real choice is whether to use > SHOULD at all. > > If you can identify the consequences without knowing the conditions, > then that does seem like a good compromise. > > (Note that while unexplained SHOULDs bother me, I am as guilty of using > them as anybody else. It is just so *easy* to do rather than try to > anticipate all the possibilities.) > > Thanks, > Paul > > >> (3) NITs > > > > Thanks for noticing these nits - they will all be fixed. > > > > Thanks, --David (as draft shepherd). > > > >> -----Original Message----- > >> From: Paul Kyzivat [mailto:pkyzi...@alum.mit.edu] > >> Sent: Saturday, May 28, 2016 2:23 PM > >> To: draft-ietf-tsvwg-rfc5405bis....@ietf.org > >> Cc: General Area Review Team > >> Subject: Gen-ART Last Call review of draft-ietf-tsvwg-rfc5405bis > >> > >> I am the assigned Gen-ART reviewer for this draft. The General Area > >> Review Team (Gen-ART) reviews all IETF documents being processed by the > >> IESG for the IETF Chair. Please treat these comments just like any other > >> last call comments. For more information, please see the FAQ at > >> <http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>. > >> > >> Document: draft-ietf-tsvwg-rfc5405bis > >> Reviewer: Paul Kyzivat > >> Review Date: 2016-04-27 > >> IETF LC End Date: 2016-05-31 > >> IESG Telechat date: > >> > >> Summary: > >> > >> This draft is on the right track but has open issues, described in the > >> review. > >> > >> Issues: > >> > >> (Note: I am having difficulty assigning severity levels to these issues. > >> So take the leveling with a grain of salt.) > >> > >> Major: 1? > >> Minor: 1 > >> Nits: 3 > >> > >> (1) Major? - Scope and Audience > >> > >> I had difficulty understanding the intended scope of this document, and > >> the intended audience. It seems to want to be a variety of things. > >> > >> * It seems to be a fine reference about congestion control for > >> applications of UDP. > >> > >> * It also seems to be pretty helpful in challenging developers about > >> whether they should be using UDP or something else. > >> > >> Probably everyone contemplating using UDP ought to read this for that > >> stuff. Those topics would be a good focus for the document. > >> > >> Beyond that it delves into a seeming random assortment of additional > >> specialized uses of UDP. These may be of interest to some, but I suspect > >> many won't find these things useful. And the topics covered seem to be > >> simply what came to mind rather than being in some way exhaustive. > >> > >> Also, some applicability to congestion control for non-UDP protocols > >> (those layered directly on IP) is claimed. This seems a bit of an > >> afterthought, and incompletely covered. > >> > >> After diffing this document against RFC5405 I see that it really is an > >> incremental change that leaves the scope largely unchanged except for > >> the addition of multicast. So perhaps I am too late to question the > >> scope of the document. But since this *is* a bis, it might be worth > >> considering whether the scope could be focused by splitting some of the > >> material off into a different document(s). > >> > >> (2) MINOR? - use of SHOULD > >> > >> I was struck by how much SHOULD is used in this document, and how > >> infrequently MUST is used. And while possible justifications for > >> violating SHOULD are sometimes provided, they often are not. In my > >> experience there has been a growing awareness that such vagueness is > >> problematic, because many implementers take it as free license to treat > >> SHOULD as MAY, and just not do it. > >> > >> (IIUC, in a BCP the normative language is relative to best practice. So > >> if MUST is written and you don't do it then you aren't following best > >> practice. But if SHOULD is written without qualification, and you don't > >> follow it then you can probably claim that you are still following the > >> best practice as documented by the document.) > >> > >> I note that most of the SHOULD usage is inherited from RFC5405, so there > >> is some justification for just leaving it be. But it could be a helpful > >> exercise to review all this usage, and consider whether usages of SHOULD > >> can be changed to MUST, or if valid justifications for violating the > >> SHOULD can be stated. > >> > >> (3) NITs: Section 3.1.7 > >> > >> In the following: > >> > >> The set of mechanisms requires for an application to use ECN over UDP > >> are: > >> > >> s/requires/required/ > >> > >> In the following: > >> > >> [RFC6679] provides guidance an example of this support, by describing > >> > >> s/guidance/guidance and/ > >> > >> In the following: > >> > >> In general, packets may be forwarded across multiple networks the > >> between source and destination. > >> > >> s/ the// > >> > >> (4) NIT: Appendix A: > >> > >> I couldn't parse the following sentence as written: > >> > >> MPLS-in-UDP endpoints must check the source IPv6 address in addition > >> to the destination IPv6 address, plus the strong recommendation > >> against reuse of source IPv6 addresses among MPLS-in-UDP tunnels > >> collectively provide some mitigation for the absence of UDP checksum > >> coverage of the IPv6 header. > >> > >> I think it would better reflect the intent if it is changed as follows: > >> > >> s/MPLS-in-UDP endpoints must/The requirement for MPLS-in-UDP endpoints > to/ > >> > >> (5) NITs - unlinked references > >> > >> I found a number of cases where, in the html format, references are not > >> hyperlinked: > >> > >> [RFC5405] section 1 > >> [RFC4342] section 3 > >> [RFC6679] section 3.1.7 > >> [RFC1981] section 3.2 > >> [RFC6935] section 3.4.1 > >> > > > > _______________________________________________ Gen-art mailing list Gen-art@ietf.org https://www.ietf.org/mailman/listinfo/gen-art
