Hi
I have 2 questions on fragmentation.
1.
The 802.11 spec says "The MAC may fragment and reassemble directed MSDUs or MMPDUs."
Practically are the management frames fragmented?
The largest unicast frame would be the authentication frame 285 bytes.If the fragmentation threshold is lesser than 285 bytes then the management frames are fragmented.
If the management frames are fragmented then provision should be provided for assembling the received fragments on the Rx side.

2."All STAs shall support the concurrent reception of fragments of at least three MSDUs or MMPDUs" why is this required.
My understanding is one a Tx STA acquied the medium no other STA would contend until all the fragments of the former STA are transmitted (Inter Frame Spacing between a fragment's ACK and subsequent fragment is only SIFS) .
In such a scenario how can another STA transmit the data?
If the assumption is true then there is no need for the Rx STA to support concurrent recxeption.

Thanks in advance