While it hasn't exactly been a detriment to their widespread adoption, RFID tags have proven to be relatively easy to exploit
in a number of cases
. Some researchers at the University of Arkansas say they've now found a novel way to change that, however, with a new method that effectively amounts to a "fingerprint" for RFID tags. The short of it is that they discovered that each RFID tag has unique minimum power response at multiple radio frequencies, and that power responses across tags were significantly different, even for tags of the same model. That, along with several other unique, unspecified physical characteristics allowed them to create an electronic fingerprint that's tied to each RFID tag, but doesn't actually depend on any modifications or encryption on the tag itself -- which almost incidentally means it can be implemented with relative ease and at no added cost.