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Benno Blumenthal wrote: > John Caron wrote: > >> Much harder question is the distinction between a dataset and a >> collection, >> since a dataset is a collection of data. I have conceptualized it as >> >> follows: a dataset is something that can be selected, and then it is >> >> processed in a protocol-dependent way. A collection is a >> protocol-independent mechanism for grouping datasets. > > I think this is what is getting us into trouble. The concept of a > dataset should be independent of the services available for it: a > dataset served from two different servers could very well have > different services/protocols available, depending on the server. (the > aggregation server converts collections to datasets, for example). > Yet from the THREDDS/educational point of view, it is the same object. > > I agree with this as well. I've been trying to reconcile how a catalog might look for a particular multifile 'dataset' which has both WMS and DODS access available for it. For WMS (for multifile) datasets the access point would be at the collection level, while for 'non-aggregated' datasets the DODS access would be lower than the collection level, at the THREDDS dataset level. It seems that the concept of a dataset resides more at the collection level, maybe the service access binding is too tightly coupled to the dataset concept in the current draft. Dan > > Benno > > > -- > Dr. M. Benno Blumenthal address@hidden > International Research Institute for climate prediction > Lamont-Doherty Earth Observatory of Columbia University > Palisades NY 10964-8000 (845) 680-4450 > >