Information Gain in Quantum Eavesdropping

摘要: Abstract We analyse the information obtained by an eavesdropper during various stages of a quantum cryptographic protocol associated with key distribution. provide both upper and lower limit on amount that may have leaked to at end distribution procedure. These limits are restricted intercept/resend eaves-dropping strategies. The one is higher than has been estimated so far, should be taken into account in order guarantee secrecy final key, which subsequently via so-called privacy amplification.