MSDU fragmentation / Aggregation MSDU

With fragmentation the MSDU would be broken into smaller sections and each section encapsulated in an MPDU. Each MPDU is sent in a separate PPDU with the preamble of each PPDU providing a new  channel estimate. (PHY Layer)











MSDU fragmented condition:  when its length exceeds a threshold. Each fragment contains an even number of bytes and all fragments are the same size, except the last fragment, which may be smaller.

The timing relation between A-MSDU/A-MPDU/PPDU :

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