A research team at the University of Waterloo in Canada has developed a UAV driven device that can use WiFi networks to penetrate walls. The device, nicknamed Wi Peep, can fly near buildings, and then use residents' WiFi networks to identify and locate all WiFi enabled devices within seconds. The research paper was presented at the 28th International Conference on Mobile Computing and Networking. This intelligent device takes advantage of a vulnerability called "Polite WiFi". Even if the network is password protected, the intelligent device will automatically respond to access attempts from any device within the range. Wi Peep sends multiple messages to the device during flight, and then measures the response time of each message to enable it to identify the device location within one meter. Dr. Ali Abedi, an adjunct professor of computer science at the University of Waterloo, explained the importance of this discovery. "Wi Peep devices are like lights in the visible spectrum, and walls are like glass." Abedi said that with similar technologies, people with ulterior motives can track the activities of security personnel in the bank through their mobile phones or smart watches. Similarly, thieves can identify the location and type of smart devices in their homes, including security cameras, laptops and smart TVs, to find good opportunities to break in. In addition, the device is operated by UAV, which means that it can be used remotely and quickly without too many chances to be detected by users. Although scientists have used bulky and expensive devices to explore WiFi security vulnerabilities in the past, the accessibility and ease of transportation of Wi Peep are remarkable. Abedi's team built it using drones purchased in stores and $20 hardware. The team's Wi Peep test shows that anyone with professional knowledge can easily create similar devices. Abedi said: "We need to fix the 'Polite WiFi' vulnerability so that this device will not respond to strangers. We hope this work can provide information for the design of the next generation protocol." Abedi urges WiFi chip manufacturers to introduce artificial random changes in the device response time, so that the Wi Peep will lose its detection capability. (Liu Xinshe)