Information reconciliation (IR) is an important step in quantum key distribution (QKD). The error correcting codes are widely used in IR, which can also be seen as error correction. But it proved that this approach contains deleting the leaked information in practical applications. Error coding is not always a guarantee of the reconciliation. It only require of the data's consistency and security. In this paper, Author proposed an improvement scheme of LDPC code on the property of reconciliation and performed some number simulations to evaluate that method. It's shown that this method would achieve a higher efficiency than the original algorithm. Therefore, this algorithm has special important meaning to the key generation.
Information reconciliation (IR) is an important step in quantum key distribution (QKD). The error correcting codes are widely used in IR, which can also be seen as error correction. But it proved that this approach contains deleting the leaked information in practical applications. Error coding is not always a guarantee of the reconciliation. It only require of the data's consistency and security. In this paper, Author proposed an improvement scheme of LDPC code on the property of reconciliation and performed some number simulations to evaluate that method. It's shown that this method would achieve a higher efficiency than the original algorithm. Therefore, this algorithm has special important meaning to the key generation.
With the rapid improvement of quantum computing technology, quantum key distribution(QKD) is a hot technology. Information reconciliation is a key step of QKD which is useful for correcting key error. Classical message interaction is necessary in a practical information reconciliation scheme, which makes the efficiency of these protocols decreased. Therefore, some one-way information reconciliation schemes based on low-density parity-check(LDPC) codes and polar codes are proposed. Here we propose a concatenated method of IR schemes which can achieve any given error rate level without the need of interactions. Compared with the one-way IR schems based on LDPC codes and polar codes, the IR schemes based on the proposed concatenated method can get lower bit error rates after error correction, which can also reduce the communication delay and system complexity of QKD, improve the final key generation rate and enhance the practicability of QKD system.
We study the information reconciliation (IR) scheme for quantum key distribution (QKD) protocols. The IR for the QKD can be seen as the asymmetric Slepian-Wolf problem, which low-density parity-check (LDPC) codes can solve with efficient algorithms, i.e., the belief propagation. However, the LDPC codes are needed to be chosen properly from a collection of codes optimized for multiple key rates, which leads to complex decoder devices and performance degradation for unoptimized key rates. Therefore, it is desired that establish an IR scheme with a single LDPC code which supports multiple rates. To this end, in this paper, we propose an IR scheme with a rate-compatible non-binary LDPC code. Numerical results show the proposed scheme achieves IR efficiency comparable to the best know conventional IR scheme with lower decoding error rates.
Information reconciliation is an important step in both quantum key distribution and unconditional secure key distribution,with the purpose to transform the two non-identical bit strings into two identical ones by exchanging error-correcting information through an authenticated public channel.However,the present known schemes all have the problem that the reconciliation process couldn't be terminated in good time.In this paper,a new scheme for terminating information reconciliation process is proposed,the main idea is to perform r(the value of r is determined by existing experiment results) round of reconciliations first,and then use error-correcting code to check if the two bit strings are identical or not,and if not,errors are corrected.In the new scheme,the round number of reconciliations is fixed and thus a higher efficiency could be achieved,particularly in the case of bit pair reconciliation,all the information exchanged in each round between the two communicating parties,no matter it is the error correction information for error correction code or the parity check sums for bisection method,could be send to the other party all in one time,so the number of information exchanges performed on public channel could be reduced.Simulation on the scheme,which is based on bit pair reconciliation protocol and uses Hamming code or(24,12) Golay code for identical verification,is also performed.
Abstract Quantum key distribution (QKD) can provide information-theoretically secure keys for two parties of legitimate communication, and information reconciliation, as an indispensable component of QKD systems, can correct errors present in raw keys based on error-correcting codes. In this paper, we first describe the basic knowledge of information reconciliation and its impact on continuous variable QKD. Then we introduce the information schemes and the corresponding error correction codes employed. Next, we introduce the rate-compatible codes, the hardware acceleration of the reconciliation algorithm, the research progress of information reconciliation, and its application in continuous variable QKD. Finally, we discuss the future challenges and conclude.
In data post-processing for quantum key distribution, it is essential to have a highly efficient error reconciliation protocol. Based on the key redistribution scheme, we analyze a one-way error reconciliation protocol by data simulation. The relationship between the error correction capability and the key generation efficiency of three kinds of Hamming code are demonstrated. The simulation results indicate that when the initial error rates are(0,1.5%],(1.5,4%], and(4,11%], using the Hamming(31,26),(15,11), and(7,4) codes to correct the error, respectively, the key generation rate will be maximized. Based on this, we propose a modified one-way error reconciliation protocol which employs a mixed Hamming code concatenation scheme. The error correction capability and key generation rate are verified through data simulation. Using the parameters of the posterior distribution based on the tested data, a simple method for estimating the bit error rate(BER) with a given confidence interval is estimated. The simulation results show that when the initial bit error rate is 10.00%, after 7 rounds of error correction, the error bits are eliminated completely, and the key generation rate is 10.36%; the BER expectation is 2.96×10-10, and when the confidence is 95% the corresponding BER upper limit is 2.17×10-9. By comparison, for the single(7,4) Hamming code error reconciliation scheme at a confidence of 95%,the key generation rate is only 6.09%, while the BER expectation is 5.92×10-9, with a BER upper limit of 4.34×10-8. Hence, our improved protocol is much better than the original one.