The next revolution in computer science already has a name: quantum computing. Computers capable of working with the superposition of ones and zeros (using qubits, which can take both values, unlike bits, which take one or the other) are still a laboratory animal, but research is increasingly approaching the dream of developing a machine with these characteristics capable of revolutionizing everything from medicine to computer security.
The quantum era will usher in a new phase in the eternal race between defenders and attackers of our privacy. Cryptography will be the battlefield in which this war of the future will be fought, the contenders of which are already preparing for a confrontation that could take place in the coming years.
Theoretically, a quantum computer would be able to break most of the current encryption algorithms, especially those based on public keys. A quantum computer can factor at a much higher speed than a conventional one. A brute-force attack (testing all possible passwords at high speed until you get the right one) would be a piece of cake with a machine that boasts these characteristics.
On the other hand, with this paradigm shift in computing will also come the great hope for privacy. Quantum cryptography will make things very difficult for spies and cybercriminals. While current encryption systems are secure because intruders who attempt to access information can only do so by solving complex problems, with quantum cryptography they would have to violate the laws of quantum mechanics, which, as of today, is impossible.
A quantum computer would be able to break most of the current encryption algorithms.
In any case, it is still early to fear or await with enthusiasm the arrival of these algorithms. Quantum computers are neither going to start decoding passwords tomorrow, nor will they be so dangerous when, within a few years, they are finally able to do so. Predictably, the security systems that would be most vulnerable to these machines will no longer be in use when, five years from now at least, they’ve become a more everyday reality.
Until then, and as a special precaution to protect the documents and some of the more confidential conversations of a company, it wouldn’t hurt to follow some tips. The most important thing is to avoid asymmetric key encryptions such as RSA, EIGamal, or one that’s based on the Diffy-Hellman protocol. Quantum computers would be able to solve relatively easily the mathematical problems at the core of their security.