Quantum Computing

Have you ever tried to retrieve that forgotten key code for your suitcase? After one year without traveling, many of us found themselves having forgotten the combination and manually trying all permutations. The same situation, but more complex, would be to systematically try identifying that forgotten access code for an online app that you had not used for a while. Cyberattackers are doing exactly this, of course, at high speed and with increasing computing performance. The recommended security key length is thus getting longer by the year. Yet, the stepwise process to achieve this is tedious or consumes lots of computing power. Now imagine that all of these possible states could be tried in a single step. This would be good for your own number lock, but frightening for our security infrastructure. © 1984-2012 IEEE.