In the following demo, members of the Center for Internet Safety and Forensic Education and Research placed a laptop which was sending out ICMP packets inside one classroom and used HaLo to sniff along the corridor and finally located the laptop. Below is the story from the student conducting the experiment.
"I placed a laptop in a classroom in Olsen Hall. The laptop kept sending out ICMP packets every 0.1 second. I used HaLo to locate the laptop. I knew the laptop's MAC address and channel before I conducted the localization experiment.
I started the device and launched the application in a sideways corridor. I began from one side and walked to the other side. In the HaLo system, I selected the channel that the target laptop was using, and the system returned a list of MAC addresses of devices which were active on that channel. Among these MAC addresses, I selected the MAC address of the target laptop and began to locate. I then selected accelerometer as speed monitor.
I could see the numbers of captured packets from the screen. The signal indicator also recorded the maximum signal strength and signal strength of the current received packet. At the beginning, the signal strength was lower than -70(db), which meant the signal was weak. Then I walked along the corridor. I walked slow enough so that within each step I could collect at least one packet. As I moved forward, the signal strength was increasing. When I passed a door of one room, the signal strength reached maximum. After that, the signal became weak and I turned back when the signal strength was below -70(db).
I came back to the position, in which I received the maximum signal strength. Because there were two rooms at that position, with one on the left side and the other on the right side. I turned around to one room first and stepped a little bit forward, the signal strength became weak. Then I faced to the other room and stepped forward, the signal strength became stronger. I opened the door of that room and located the target."
Read about the Hand-Held Location Device (HaLo).