Kvanttisalauksen

Kvanttisalaus, often referred to as quantum cryptography, is a field that utilizes quantum mechanical principles to perform cryptographic tasks. Its primary application is in quantum key distribution (QKD), a method for generating and distributing secret cryptographic keys between two parties in a way that is theoretically immune to eavesdropping by any future quantum computer.

The security of QKD relies on the fundamental laws of quantum mechanics, specifically the properties of photons such as superposition and entanglement. If an eavesdropper attempts to intercept or measure the quantum states being transmitted, they inevitably disturb these states, alerting the legitimate parties to the presence of an intruder. This inherent detection mechanism is what gives QKD its unparalleled security.

Unlike classical encryption, which relies on the computational difficulty of mathematical problems, quantum cryptography's security is based on physical principles. This means that even if a powerful quantum computer were developed, it would not be able to break QKD. The most well-known protocol for QKD is BB84, named after its inventors Charles Bennett and Gilles Brassard, and presented in 1984.

While QKD focuses on secure key distribution, the broader field of quantum cryptography also explores other applications, such as quantum secure direct communication and quantum digital signatures. However, QKD remains the most mature and widely researched area. The development of quantum cryptography is driven by the growing concern over the potential threat posed by future quantum computers to current encryption standards, a phenomenon known as the "quantum threat."