This was session 361, part of the Wireless LAN Professional Wi-Fi Design Class, where Ferney covered the complete lifecycle of a Wi-Fi project. The session focused extensively on the definition phase, explaining that proper project definition goes far beyond simply installing Wi-Fi everywhere – it requires understanding client requirements, device types and capabilities, cabling infrastructure, budget constraints, vendor selection, power requirements, and physical mounting considerations. Ferney emphasized that Wi-Fi professionals should be involved in all stages of the project lifecycle rather than just being called in for post-deployment surveys when problems arise. The discussion included detailed explanations of design tools like Ekahau, Hamina, and Wavelify, and the importance of pre-deployment validation using “AP on a stick” testing to ensure designs work in real-world conditions. Ferney also clarified the difference between design (predictive simulation) and survey (on-site measurement), and addressed common pitfalls like the “one AP per classroom” approach that often leads to inadequate coverage.

The session focused on the concept of cell overlap in Wi-Fi network design, specifically addressing the fallacy of quantifying cell overlap as a percentage. Ferney explained that the idea of requiring a certain percentage of cell overlap, such as 30%, is not measurable or practical due to the irregular shapes of real world Wi-Fi coverage areas. He demonstrated using design tools like Ekahau and Hamina to show how secondary coverage, which provides multiple signals for redundancy and roaming, is achieved by adding more access points rather than targeting a specific overlap percentage. The discussion highlighted the need to educate customers and peers to remove such unverifiable requirements from RFPs and contracts. The session also briefly touched on the life cycle of a project, which was postponed for a future discussion.

This was session 359 of Ferney’s free Wi-Fi design class, focusing on Wi-Fi interference terminology and concepts. Ferney explained key Wi-Fi terms including Basic Service Set (BSS), Basic Service Set Identifier (BSSID), Service Set Identifier (SSID), and Extended Service Set (ESS), demonstrating how different access points announce the same SSID using different BSSIDs. The session covered various types of Wi-Fi interference such as Co-Channel Interference (CCI), Adjacent Channel Interference, and Overlapping Basic Service Sets (OBSS), along with protection mechanisms like RTS/CTS. Ferney discussed how most Wi-Fi interference comes from other Wi-Fi networks rather than external sources, and showed examples using Wi-Fi Explorer Pro to analyze interference patterns in real networks. The class included participants from around the world including Australia, France, Sweden, Italy, Chile, Canada, and the United States, with Ferney emphasizing that all session recordings would be made available for free to help train Wi-Fi professionals worldwide.

This was Session 358 of Ferney’s free Wireless LAN Professionals Wi-Fi Design class, focused on the association process in Wi-Fi networks. Ferney explained how devices discover Wi-Fi networks through passive scanning (beacons sent 10 times per second, per radio, per SSID) and active scanning (probe requests sent by clients and probe responses sent by APs), emphasizing that too many networks increase airtime utilization and overhead. The class covered the complete association process from WLAN discovery through open system authentication, association request/response frames, and finally IP address acquisition via DHCP, with Ferney demonstrating real packet captures using Wireshark to show the entire process taking 1.9 seconds. Ferney stressed the importance of keeping the number of SSIDs low to reduce beacon overhead and discussed different authentication methods including PSK and 802.1X, noting that PSK is less secure due to its vulnerability to brute force attacks when passwords are shared among multiple users.

Hello, good morning, afternoon, or evening to everyone around the world! Welcome to Session 356 of Tesos en Wi-Fi, part of the free Wireless LAN Professionals Wi-Fi Design Class. Today, on Saturday, July 25th, I decided to celebrate my birthday doing what I love most: sharing Wi-Fi knowledge with all of you 100% free!. The Frame Types Burden: Why most airtime isn’t actually carrying data, but small management and control frames. OFDM Subcarriers & Channel Bonding: How 20 MHz channels divide into 64 subcarriers, and the price we pay in spectrum congestion when bonding into 40, 80, or 160 MHz wide channels. Interference Realities: The technical differences between Co-Channel Interference (CCI), Adjacent Channel Interference (ACI), and Overlapping Basic Service Sets (OBSS). DFS & AFC Rules: How Dynamic Frequency Selection protects radar systems, and how Automatic Frequency Coordination manages standard-power 6 GHz APs. Wi-Fi 6 OFDMA Mechanics: How Resource Units allow up to 9 client devices to transmit simultaneously, shifting Wi-Fi from single-device contention to efficient spectrum scheduling.