Researchers at MIT's Computer Science and Artificial Intelligence Laboratoryhave created Wi-Fi technology that identifies where you are, which may eliminate the need for passwords.

The system, called Chronos, can determine where a user is with an accuracy of "tens of centimeters," according to the research paper. This has various uses, such as telling Chronos not to allow people beyond the walls of your home or small business access to your network, called geo-fencing. You could build virtual walls that mimic your real ones.

Inside your house? No problem. Take one step outside your front door? No access.

By telling Chronos to block Wi-Fi access to users outside of a certain area, you can keep out hackers or people trying to piggyback on your network without the need for passwords. The researchers tested this in the epitome of a small business that relies on Wi-Fi, the coffee cafe, and found it to work with 97-percent accuracy. They tested home use also, finding that Chronos could identify four users and what rooms they were in with 94-percent accuracy.

The exact method Chronos uses to accomplish this feat is interesting and a little involved. Roughly speaking, the system can judge how long it takes for a Wi-Fi signal to get to a device using it (called time of flight) with an error rate of 0.47 seconds. By calculating that and multiplying it by the speed of light, Chronos can determine both the angle (i.e., the cardinal direction) and the distance of the device relative to the router, giving it more or less exact coordinates. According to the researchers, this is 20 times more accurate than existing systems.

Researchers suggested other uses as well, such as coupling with smart home technology to automatically warm and cool, or turn on and off lights when you move into another room. They also demonstrated how Chronos can keep a drone within a certain distance of someone, so it could either follow you around or prevent itself from bumping into you.

Will hackers figure out a different way to get into your network? The paper is mum on the subject. Forging your time of flight seems more than difficult, but hacking networks may easily move into territory beyond breaking passwords.