It is in the interest of some parties, such as hackers, law enforcement, intelligence agencies, etc, to break this encryption and gain access to the data contained within. Brute force attacks is one method used to discover the key needed to unlock the data. It is by far the most rudimentary cracking process, involving trying every combination possible. Imagine forgetting a friend's phone number and starting at 100 - 0000. And since guessing the right number gets exponentially harder every time a new number set is introduced it could take years to do even for the fastest dialer. In the same way computer systems, hardware or software, attempting to crack a key are limited by power, heat and other variables, as described in the laws of thermodynamics, making extremely long keys impractical to crack.