Researchers have devised a system that can recognize a user’s keystrokes by exploiting available WiFi signals. The “WiKey”” system works because most WiFi devices (including routers) come with multiple-input and multiple-output (MIMO) capabilities. Researchers used a TP-Link TL-WR1043ND WiFi router and a Lenovo X200 laptop to identify a user keystroke. WiKey registered a 96.4 percent success rate in classifying single keystroke
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