As we move into the digital age, everything is only secure if it's up to date cryptographically. Cryptography is the foundation of safe communication. It protects everything from daily personal messages to secrets concerning national security. Existing and traditional systems of cryptography such as RSA, Elliptic Curve Cryptography (ECC), and Diffie-Hellman have been around for decades and stand up to attacks by classical computers. They enjoy widespread trust on our internet, banking, government, and healthcare systems. However, as useful as quantum computing has the potential to be, it disrupts decades of established systems of digital security.
Quantum Computers operate by fundamentally different, and better, rules than classical computers. Computers operate on bits, with a bit being either on or off, or 1 or 0. Quantum computers operate on quantum bits, or qubits, and leverage things like superposition and quantized entanglement to solve problems typical computers cannot solve, or to solve problems that would take a typical computer billions of years to solve. Quantum computers are not there yet, but they will be able to break widely used algorithms that traditional computers are inefficiently simulating. Shor's algorithm, developed in 1994, factors large integers exponentially faster than classical algorithms, directly affecting RSA and ECC. Grover's algorithm can also reduce the security of symmetric key algorithms, requiring longer key lengths.