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Hi Mark
In general this looks OK to me, but I recall a previous discussion about whether the User Priority field in TCLAS element is an “input” or “output”, which could be relevant here.
In cases where the UP is an “output” (i.e. that UP is assigned to MSDUs that match the filter), it probably makes sense that the Frame Classifier field is not completely wildcard (although I’m not sure it hurts to allow that possibility).
OTOH, in the specific case of TFS which was identified in the previous thread, it seems the UP field (when it takes values 8 thru 11) is an *input* for MPDU classification, i.e. it’s effectively part of the classifier itself. Then, might there be a use case where the only required filter is the AC of the MPDU, and no other filters (e.g. MAC addresses, IP tuples) is necessary? If so, given the Frame Classifier field must be present, it might need to specify a wildcard classifier..
Thanks Thomas
I haven't seen any response to this post, so should I conclude that there is no objection to resolving this comment as: REVISED At the end of 9.4.2.30 add: 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. ? Thanks, Mark -- Mark RISON, Standards Architect, WLAN English/Esperanto/Français Samsung Cambridge Solution Centre Tel: +44 1223 434600 Innovation Park, Cambridge CB4 0DS Fax: +44 1223 434601 I was asked to start a thread on this comment: CID 1859 | 9.4.2.30 | 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 masks: 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 9.4.2.30: 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. Thanks, Mark -- Mark RISON, Standards Architect, WLAN English/Esperanto/Français Samsung Cambridge Solution Centre Tel: +44 1223 434600 Innovation Park, Cambridge CB4 0DS Fax: +44 1223 434601
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