BB84

Common card · No. 398858

The BB84 protocol, named after its inventors Charles Bennett and Gilles Brassard in 1984, is a prepare-and-measure quantum key distribution (QKD) protocol, in which, one party (e.g. Alice) performs the encoding by preparing the quantum states, and the other party (e.g., Bob) measures them. The BB84 QKD scheme is the first quantum cryptography protocol, and has become one of the most well-studied QKD protocols. The protocol is provably secure assuming a perfect implementation, relying on two conditions: (1) the quantum property that information gain is only possible at the expense of disturbing the signal if the two states one is trying to distinguish are not orthogonal (see no-cloning theorem); and (2) the existence of an authenticated public classical channel. As such, the security of the BB84 protocol is fundamentally based on the principle that two non-orthogonal quantum states cannot be perfectly distinguished. This inherent limitation means that the states cannot be reliably copied...

Read on Wikipedia