Hoi - Kwong in the Secure QKD ", mentioned in a recent QKD security called "composable" theoretical definition has been proposed. QKD network has been in the United States, Austria, Switzerland, China and Japan started deploying. At the same time, QKD system is also used to guarantee the votes in the Swiss national elections transmission security. In 2010 FIFA World Cup in durban, South Africa, also use the QKD system to protect the security of the communication line. In addition, QKD system backup can also be applied in other cities, enterprise private network, critical infrastructure protection, protection and high confidential network backbone authorization, etc. In short, QKD technology has been more mature in the practical application.
QKD is mature in theory. BB84 protocol, is an important milestone in the history of quantum communication. The protocol used to describe how to use the photon polarization to transmit information, to set up between two remote users unconditional security of quantum key provides a powerful way. Quantum key distribution has experienced more than 20 years of development, the security of transmission distance 32 cm from the initial development to more than 200 km.
In 1989, Bennett, Bessette and Brassard connection tome Kerr cell by LED a successful implementation of 32 cm the experimental demonstration of quantum key distribution; In 2007, Ursin based on quantum entanglement in the canary islands, 144 km away from the La Palma island and Tenerife island successfully established quantum key distribution system; Jian-yu wang and others in 2013, for the first time in the world star is implemented in the full range of quantum key distribution verification on the ground, for the future implementation based on the star to the quantum world of quantum communication network laid a solid technical foundation; In November the same year, jian-wei pan academicians and his colleagues successfully the extension of the safe distance of quantum key distribution system to 200 kilometers, set a new world record.