802.11 is Layer 2 and Layer 1. After frames come to Layer 1 from PPDU pre 802.11-2016 standard shows there are two interfaces PLCP and PMD as show below. NOTE: Per 802.11-2016 there is no longer PMD and PLCP, please read this article R.I.P. PMD by Robert Haviland explaining it really well. Since my post is very specific to CWAP – 403 Certification that is still including those two interfaces I am creating the flow accordingly for my quick reference:
Based on different 802.11 PHY’s, there is a quick reference chart showing different modulation and Coding along with different data rates
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