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[STDS-802-11-TGM] 11me/D1.0 CID 1859 (all-zero Classifier Mask fields)

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I was asked to start a thread on this comment:


CID 1859

It is not clear whether it is OK to have a Classifier Mask field (where it is not reserved) that is all-0, and if so whether that is an "always matches" or a "never matches"

At the end of the subclause add "If a Classifier Mask field is present and all bits that are not reserved are 0, then this classifier never matches."


As far as I can tell, the classifiers have the following classifier



0, 1, 2, 4, 5: bitmap indicating parameters that need to match

6, 7, 8, 9: bitmap with 2-bit subbitmaps

3: reserved

10: not present (despite what Figure 9-364—Frame Classifier field format says -- see CID 1856)


The direction of the group was to specify that classifiers that

don't classify anything shall not be transmitted, rather than

trying to specify that they never or always match.


Because there are so many classifiers, and they classify in quite

significantly different ways, I propose adding this general statement

at the end of


A classifier classifies on the basis of at least one match.

NOTE---For example, when the Classifier Mask field is present and

not reserved, at least one bit of this field that is not reserved is set to 1.







Mark RISON, Standards Architect, WLAN   English/Esperanto/Français

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