Fingerprinting (WLAN)
Under Fingerprinting in WLANs refers to the recording of existing wireless -Signalen at a certain place and at a particular time. As a rule, "broadcasts" broadcast by WLAN routers are recorded. By recording the MAC addresses , the names of the WLANs broadcast ( SSID ) and the reception strengths of the incoming broadcast signals ( RSSI ), a characteristic "fingerprint" of the WLANs can be created at the location of the measurement.
Use for position determination
Localization can be carried out later on the basis of the recorded data. This is particularly useful in buildings and closed rooms where GPS cannot be used to determine your position. For this purpose, mobile devices, such as smartphones , are equipped with software that uses the captured fingerprints to calculate where the device is currently located. To do this, the device first records a fingerprint of its current location and compares it with the stored data. In this way, the software can determine whether the device is in the vicinity of known hot spots .
Practical use
There are implementations of the above-mentioned position determination method , such as Intel's PlaceLab , but the technology is only used in a localized manner, since a sufficient number of fingerprints must be recorded for this.
As part of the Street View project, the search engine operator Google has been experimenting with the aforementioned methods of position determination for a long time and, in many countries, uses its “Street View Cars” to record not only the surroundings and the GPS position but also the WLANs available at the respective location. In Germany, however, Google was banned from fingerprinting across the board for reasons of data protection law.
Individual evidence
- ↑ Intel's PlaceLab ( Memento of the original from August 21, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Google stops collecting WiFi data . In: FAZ , May 15, 2010
