Summary: In this episode, I talk with Francois Verges of Semfio Networks about how to validate the Wi-Fi infrastructure.<br> Validating a Wi-Fi network involves many steps. This is not isolated to a new deployment but also to an existing Wi-Fi network. Francois and I talk about what to validate, look out for, and what resources are available to assist on the job.<br> Validate Physical Installation<br> <br> * Walk through the facility<br> * Validate<br> <br> * AP installation<br> * Antenna orientation<br> * With the customer<br> * Telco room location<br> <br> <br> <br> Post Deployment Survey<br> <br> * Use your survey laptop and try to use a business critical business device as well (VoIP phone, handheld scanner…)<br> * Connect to the infrastructure. Use the most business critical SSID.<br> * Use Ping or iPerf to test connection, roaming, throughput.<br> * Things to look at while performing the exit survey:<br> <br> * What band is the survey laptop using?<br> * What band is the client device using?<br> * Am I roaming as expected<br> * RSSI of both your laptop survey and the client device<br> * If you use ESS, you can also connect 1 or 2 dBx antenna to perform a parallel spectrum analysis. (Detect noise and major interferences)<br> <br> <br> <br> Things to look at after the survey:<br> <br> * Coverage<br> * Channel distribution / Channel re-use<br> <br> * See if some Tx Power need to be adjusted<br> * See if some radios need to be disabled (2.4GHz)<br> * See if more 5GHz channels are needed<br> * Making sure that all the configured channels are being used.<br> <br> <br> <br> Spectrum Analysis<br> <br> * Study both bands: 2.4GHz is usually where you will find the most external interferences<br> * Stay still at one location. If you see something unusual, move around to pin point the exact location of the source. (might not be easy). – Plan for a little extra time.<br> <br> Packet Capture<br> <br> * Get a better idea of the RF environment (using Eye P.A.). Thing to look at:<br> <br> * Retry rates<br> * Channel airtime utilization<br> * Data rates<br> * How the neighbours can be affecting some channels<br> <br> <br> * Being able to see more advanced radio configurations such as:<br> <br> * data rates<br> * AP capabilities<br> * Client capabilities (Big one)<br> * Being to spot unusual behaviours<br> * Being able to troubleshoot some client issues<br> <br> <br> <br> Analyze Client Behavior and Configuration<br> <br> * Make sure all the client devices of the same model have the same Wi-Fi NIC drivers<br> * Make sure all the client devices of the same model have the same Wi-Fi configurations<br> * Make sure they manage to connect to the Wi-Fi network (Check delays, does it take a long time to connect?)<br> <br> Perform Functional Validation Testing<br> <br> * Grab a client device, roam around the facility (especially where the device will be used)<br> * Validate how the client roams<br> * Validate on what band the client connect to<br> * Try to ping the application server and see if you lose any pings (make sure it does not affect production)<br> * Validate voice quality if it’s VoIP<br> * Validate throughput if the requirements need it (try to use the same applications as the one what will be used on the Wi-Fi)<br> <br> Links and Resources<br> <br> * <a href="http://transmitfailure.blogspot.com/2016/08/why-validation-surveys-arent-enough.html" target="_blank" rel="nofollow">Jake Snyder blog</a><br> * <a href="https://www.cleartosend.net/when-how-to-use-spectrum-analysis/" target="_blank" rel="nofollow">CTS 039</a> – When and How To Use Spectrum Analysis<br> * Mike Albano – <a href="http://clients.mikealbano.com" target="_blank" rel="nofollow">Clients</a><br> * <a href="https://www.cleartosend.net/cts-009-jussi-kiviniemi-of-ekahau/" target="_blank" rel="n..."></a>
