Intel is developing a way to locate a Wi-Fi user by timing how long it takes for packets to travel to and from a wireless access point. The idea is that users outside a house or office could be prevented from accessing a Wi-Fi network indoors, providing additional network security.
Precision location technology is one of several key ideas for the next few years that Justin Rattner, Intel senior fellow and director of the company's Corporate Technology Group, showed off during a keynote presentation on the last day of the Intel Developer Forum last week.
Knowing where a system is located also could be an invaluable aid in finding and fixing hardware problems in data centres and for informing mobile device users of places or services nearby, Rattner said. Satellite-based GPS works well outdoors but generally not indoors, he said. Triangulation among Wi-Fi access points based on signal strength is available today indoors but is not precise enough for many uses, Rattner said. This led Intel to study other systems.
In the technology demonstrated Thursday, the access point times how long it takes a packet to travel out to the client system and come back. From the length of that round-trip time, it can extrapolate how far away the client is, Rattner said.
The technology is so precise, even up to 70 meters from the access point, that it can tell whether a client device is inside or outside a wall, Rattner said. For keeping neighbours or passers-by from intruding on a home or enterprise network, it might even be more effective than current encryption systems, he added. Another possible use of the location technology demonstrated at the show was to make a video program follow a user from room to room. For example, if a user carried a notebook PC, the program could move from a TV in the living room to a large PC monitor in an office and then come up on the notebook when the user got out of range of either stationary display, he said.
Both access points and clients would have to be modified to support the system. Intel plans to bring the technology to the IEEE 802.11 group for standardisation, he said.