SOUZA, M. A.; SOUZA, Micael Andrade.
Resumo:
The quantum secret key distribution is one of the main practical applications of quantum
information theory, making use of quantum mechanics laws’ to ensure unconditional se-
curity on information transmission through quantum states and allowing two parties to
securely share a secret key with no need for previous shared information. In this work,
a solution for secret key reconciliation is presented for keys generated by CVQKD distri-
bution schemes using the established CASCADE reconciliatiion protocol. Although it is
traditionally applied in the reconciliation of keys generated by DVQKD schemes, which
results on bit error rates lower than 0.15, its use is made feasible in the context of continu-
ous variables by means of proposed modifications in the initial block size and the number
of reconciliation steps executed. This work proposes modifications on fundamental pa-
rameters of the reconciliation protocol such that (1) a compleat secret key reconciliation
be realized where the bit error rates are lower than 0.25 and (2) a partial reconciliation
solution for secret keys with bit error rates greater than 0.25, which aims to control the
amount of corrected errors during reconciliation by the amount of leaked information.