# Problem

Locks and Keys

The problem we’re analyzing is very simple to grasp and likely is familiar to anybody with a background in security. Firstly, cryptography is used to encrypt information for any user that wants their information to remain relatively private between them and the party they’re interacting with. This is done in a variety of ways, but for simplicity’s sake, it only needs to be visualized as a lock and keys. Only 1 key fits the lock, but you don’t know which key to use. Given enough keys, it’ll be mathematically impossible to try all of them, even with a powerful computer.

The most basic example of a lock would be a cipher where “each value is entered into the [equation] C = P + 3, where p is the plaintext value and C is the ciphertext value” (Olmanson, 8). The lock is the formula itself, being the thing you put your unencrypted information into. The key is your information, which is converted to a unique encrypted value. While this cipher is easy to crack, even as a human, the more complicated ciphers use prime numbers in a way that makes it impossible to reverse the function. This means a computer is forced to guess each value that it could be, one after another, forming the basis for why higher computational speed leads to faster decryption of unknown information.

Quantum Computers

This is where quantum computers step in, having the higher computational speed required for cracking the most complicated locks. When examined from a mathematical standpoint, “quantum computers have been shown to have exponential speedups” (Bernstein et al., 2009, p. 17). By being capable of trying more keys, much faster than a classical computer, a quantum computer can eventually find the right key to the lock. This creates a larger issue than might be initially expected because not every single lock (cryptography method) is unique across the internet. While they have different pins (private/public keys), they are still fundamentally made the same way. That means if a quantum computer can crack 1 lock type, they can crack all locks of that same type.

Repercussions

In a world where cryptography can be more easily breached, everybody takes a toll. This is because cryptography is absolutely everywhere and in everything, used to secure most communications over the internet for the sake of privacy. If not addressed, it will also take a greater toll on the programmers and developers that have to create a new quantum-proof solution. The time needed to create said solution would take even longer than expected due to potential issues that arise from the sheer number of people who will be available to test it. A quantum proof solution made in the moment will be put through a “trial by fire” because of all the people who use cryptography, which is unfavorable for anybody wanting reliable security.