1) Aruba AP Tunnels — Architecture & Forwarding A. Big picture In Aruba’s controller–based architecture (Campus AP / RAP), each AP: Discovers one or more controllers (L2 ADP, DHCP option…
The three amendments that made Wi-Fi enterprise-ready: 802.11h DFS and TPC for coexisting with radar, 802.11e/WMM EDCA access categories and DSCP mapping for voice and video, and 802.11i RSN with its key hierarchy and 4-way handshake — plus PMF (802.11w), WPA3, Enhanced Open, and a Wireshark checklist for verifying all of it in a capture.
How 20 MHz channels are bonded into 40, 80, 160 and 320 MHz channels — primary and secondary channels, dynamic bandwidth, preamble puncturing and the capacity trade-off — followed by the 802.11 MAC header, the four address fields, and management, control and data frames with reason codes and Wireshark filters.
The maths and physics behind Wi-Fi signals: dB and dBm, EIRP and ERP, antenna gain, types and patterns, received signal strength, noise floor and SNR, receiver sensitivity per MCS, free space path loss and wall attenuation, link budgets in both directions, and OFDM — subcarriers, orthogonality, guard intervals, pilots and how to calculate a data rate from first principles.
Wi-Fi's three frequency bands in depth: the 2.4 GHz ISM band and the 1-6-11 rule, 5 GHz UNII-1 to UNII-4 with DFS and weather-radar channels, 6 GHz UNII-5 to UNII-8 with preferred scanning channels and LPI/Standard Power/VLP power classes and AFC, channel numbering, regional differences, range versus capacity, and channel-planning guidance.
The foundations of Wi-Fi: who defines it (IEEE, Wi-Fi Alliance, regulators), the 802.11 generations from 802.11b to Wi-Fi 7, the 802.11 MAC and PHY, BSS/ESS architecture, CSMA/CA and the hidden node problem, how a client joins a WLAN, bands, modulation and MCS, MIMO/MU-MIMO/OFDMA, and Wi-Fi security from WEP to WPA3.