IEEE802.11e supports multiple (8) priority streams mapped to IEEE802.1D
priority tags and in turn mapped to DSCP values. When DTLS-protected, the
CAPWAP dataflow, potentially carrying these multiply tagged streams, may get
reordered along the way to AC (or vice versa) leading to spurious replay
flagging at the receiving end (AC or WTP).
The proposed approach to resolve this is to use the DTLS session resumption
feature to create new sessions (it does not invalidate existing DTLS session
between the said WTP & AC) and map one to each priority stream in use. The
preamble header is used to carry the priority. The mapping is negotiated over
control path.
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