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Object Identifiers are names assigned to things. Object Identifiers vary from abstract classes to actual items and from logical object to physical devices. All of these things and more are named. I think that the term "classes" needs some additional modifiers, e.g., classes of what? I also suggest that "actual items" is vague,. A more definitive terms is needed, but I am unclear on what we are trying to say here to make a suggestion.
On Object Identifiers vs ITU-T OIDs
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