I was reading the wiki on magnetic stripe cards when I stumbled across this sentence: "Magnetic stripe cloning can be detected by the implementation of magnetic card reader heads and firmware that can read a signature of magnetic noise permanently embedded in all magnetic stripes during the card production process." (wiki cites this page)
In an ideal case, a new card would be made and its magnetic fingerprint (or a hash of some kind) would be uploaded to a database. So let's say
CC 4224 9450 9930 2192 has a hash of
2ca52df6. The hash
2ca52df6 could easily be stored on the remote computer that a card uses to check its balance. The integrity of the card would be verified by quickly creating a hash of the card's magnetic noise and then transmitting that, along with the CC info, to the remote server for verification. Since magnetic noise is so unique to each card, the chances of the hashes of a legitimate CC matching a cloned CC are slim to none.
This seems pretty straightforward, which leads me to think I am missing something. Granted, credit cards have long outlived their life span, but why has a feature like that not been implemented in the 40-50 years magnetic stripe technology has been around?