The rapid growth of computer power coupled with the increasing sophistication of attackers is pushing the limit on this security. The development of the ultra-fast quantum computers is making things worse by forcing the asymmetric key solution providers to enlarge the key length. A couple of years ago 256 bit keys where declared as “military safe”. Then the key length grows from 256, 512, 1024, and 2048 to 4096 bits actually. This is a run-away situation that will continue until the key is as long as the message itself! In this moment, the asymmetric public, private key systems will turn into a symmetric key solution, the so called One Time Pad, with only one key that is as long as the message itself.
You can’t use publicly available encryption systems because they’re all compromised.”
(William Edward Binney, former Technical Director at NSA. Keynote at the Munich Conference for Strategic IT-Management 2014)