----- Original Message ----- From: "Ben Campbell" <ben@xxxxxxxxxxx> Sent: Tuesday, September 11, 2018 5:40 PM > On Sep 11, 2018, at 11:31 AM, tom petch <daedulus@xxxxxxxxxxxxx> wrote: > > Ben > > I don't understand it! In particular > > 'Normative updates that do not use a known extension point should always > include an “Updates” header.' > > leaves me ignorant. > > 'Normative' I am well familiar with from I-D references but that meaning > does not seem to apply here (since Normative as a Reference means you > must understand the referenced work).. > > '..known extension point..' I am not familiar with except for a rather > technical discussion which I read - but did not understand - on this > list recently. A known extension point is any mechanism in the original RFC designed to allow extensibility without modifying the RFC. IANA registered code points are a common approach. Feature negotiation mechanisms also come to mind. Can you suggest a better term for this? Ben No:-( I understand your explanation and see that concept in many places, but do not know of any generic term for it. (Thus I think of YANG augments, but that term would probably not make sense to those not versed in YANG). Rather, I would like to see your sentence of explanation or something like it in the statement. Tom Petch > To give a practical problem; when an I-D adds new entries to an existing > registry, is that an 'Updates'? I have seen ADs firmly tell WG Chairs, > holding the contrary opinion, that it is not, and I thought that that > was settled, but applying this statement to that situation leaves me in > ignorance. The intent is that these are usually not “Updates”. But they can be if there are special circumstances, which I presume would be documented in the text that describes the nature of the update. An individual AD may or may not agree with an argument that a particular update is “special” in this sense, but I believe we all agree that such special cases are in the realm of possibility. Thanks! Ben. > Tom Petch > > > ----- Original Message ----- > From: "Ben Campbell" <ben@xxxxxxxxxxx> > To: <ietf@xxxxxxxx> > Cc: "The IESG" <iesg@xxxxxxxx> > Sent: Tuesday, September 11, 2018 4:55 PM > > Hi Everyone, > > There have been several discussions lately about the use and meaning of > the “Updates” header in RFCs, and the resulting “Updates”/“Updated by” > relationships. The IESG is thinking about making the following > statement, and solicits feedback. > > Thanks! > > Ben. > -------------------------------------------- > > There has been considerable confusion among the IETF community about the > formal meaning of the “Updates” / "Updated by" relationship in IETF > stream RFCs. The “Updates” header has been historically used for number > of reasons of various strength. For example, the “Updates” header may be > used to indicate critical normative updates (i.e. bug fixes), optional > extensions, and even “additional information”. > > The IESG intends these headers to be used to inform readers of an > updated RFC that they need to be aware of the RFC that updates it. The > headers have no formal meaning beyond that. In particular, the headers > do not, by themselves, imply a normative change to the updated RFC, nor > do they, by themselves, imply that implementers must implement the > updating RFC to continue to comply with the updated one. > > The specific reasons that a given RFC updates another should be > described in the abstract and body of the new RFC. The level of detail > may differ between the abstract and the body; typically an abstract > should contain enough detail to help readers decide if they need to read > the rest of the RFC. The body should contain enough detail for readers > to fully understand the nature of the update. > > The importance of including an “Updates” header depends on the nature of > the update. Normative updates that do not use a known extension point > should always include an “Updates” header. Extensions that do use known > extension points do not typically need to include the “Updates” header, > but may in cases where it’s important to make the extension known to > readers of the original RFC. Other uses of “Updates” may be appropriate > when it’s important for readers to know about them; for example a new > RFC may expand security or operational considerations in a way that is > not normative, but still important. > > RFCs that fully replace other RFCs should typically use the “Obsoletes” > header rather than the “Updates” header. The “Updates” header should be > used to flag updates to published RFCs; it is not appropriate to > “Update” an Internet-Draft. >
