Well, the measurements are data points that include many many factors -- from the link rate and signal quality between the different mesh points, to the link between the PC and the mesh point, to the tuning of the wifi radios, the pyhsical characteristics of the environment (construction materials, etc.) that can have an effect on the performance of wifi, the wifi radio capabilities in the AP, and also the capabilities in the PC.... the list goes on. You can try to troubleshoot/characterize those things, but it also depends how much effort you want to put into it and what practical improvements you think you can make.
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