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Limits RegistryCharles Bennett of IBM and Gilles Brassard of the Université de Montréal presented BB84 at a 1984 conference in Bangalore, India. Alice encodes random bits in one of two conjugate polarization bases; any eavesdropper unavoidably disturbs the states and is revealed by errors. BB84 underlies most deployed QKD systems.
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Charles Bennett of IBM and Gilles Brassard of the Université de Montréal presented BB84 at a 1984 conference in Bangalore, India. Alice encodes random bits in one of two conjugate polarization bases; any eavesdropper unavoidably disturbs the states and is revealed by errors. BB84 underlies most deployed QKD systems.
The year Bennett and Brassard published BB84, the first protocol for distributing secret keys with security guaranteed by quantum mechanics.
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Permanent ID limitsregistry.com/limits/LR-BB84-FIRST-QKD-PROTOCOL
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Limits Registry. LR-BB84-FIRST-QKD-PROTOCOL. First quantum key distribution protocol (BB84). 2026.