Quantum Computer Encryption Analysis

In modern society, we have instant access to seemingly endless amounts of information. Millions of Bytes of data are sent through the internet every second. Large quantities of sensitive data are stored and delivered. With so much traffic the need for secure systems to ensure no data end up in the wrong place arises. Fortunately, we already have many methods of ensuring secure data transfer, but with the advent of quantum computers some encryption will inevitably become obsolete.

To understand why quantum computers pose a threat to current encryption methods we first have to understand two things: How modern encryption works and how quantum computers differ from normal computers.

The science of cryptography is about sending messages that can only be understood by the sender and the recipient. The most basic, and when its only flaw is overcome the potentially safest, way of encrypting a message is by using symmetric encryption. This means that both parts have a “key” that can both encrypt a message (scrambling the message) and decrypt a message (reversing it back to its original form) which has been encrypted with that key. The only problem with this encryption type is that the key has to be known by both parties and the method does not include any way to send the key

While a traditional computer process data as a stream of 1s and 0s (called bits (binary + digit)) a quantum computer relies on the peculiar effects of quantum physics. On the miniscule scale of quantum physics a particle can be in two opposite states simultaneously. This property allows a qubit (the quantum computer equivalent to a bit) to be in three different states; 1, 0 or both 1 and 0 at the same time. Because of this, quantum computers unlock a whole new dimension of computing. A sufficiently powerful quantum computer could factorise a product of two very large primes in a matter of seconds rendering anything encrypted by RSA extremely