On Aug 31, 2011, at 9:12 AM, Hector wrote: > Keith Moore wrote: >> On Aug 31, 2011, at 8:30 AM, Hector wrote: >>> In my view, SHOULD are user protocol options to set. >> In my view, SHOULD should rarely be used for optional protocol features, because optional protocol features should themselves be rare. And the primary purpose of SHOULD is not to permit optional protocol features. > > If SHOULD is read as a MUST IMPLEMENT, and that also implies MUST USE with no provision to disable then its should of been a MUST in the first place. Just because a feature is optional does not mean that it's a protocol feature... i.e. it doesn't mean that it affects how the implementation interacts with peers. SHOULD is IMO most often useful not when specifying how a protocol acts "on the wire", but when specifying how a protocol needs to be implemented on a particular platform, where the precise semantics, API details, etc. naturally differ from one platform to another. > Why even bother with SHOULD, and use have MUST and MAY? To get people out of the rathole of trying to specify exactly how everything must work in excruciating detail, in a world where there is inherently going to be some necessary variation. Keith _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf