BB84 protocol simulation with applying of cascade error correction method

The most important security problem is key detection and sharing that cannot be predicted, in key shared cryptography methods used in data communication. Therefore, it is necessary to use medium that is hard to predict and listening can be determined. For this reason, the behavior of the photons in the fiber line is used in determining the key in the quantum cryptography method. In this method, a private key is generated between the sender (Alice) and the receiver (Bob). Alice creates four photon polarizations using two linear and diagonal filters (+ and X). The photons that Alice produces with her filter are passed on to Bob's randomly generated filter. The shared key is produced with matching filters. The shared key generated by Alice and Bob will not be similar, because of the noise in the quantum channel, or a listener (Eva) intervening. The error rate of photons passing through the channel should be less than 27.6%. If the error rate is above this threshold value, the communication should not be performed. In this study, BB84 Quantum key distribution protocol, used for generating keys in noisy environments during operation, is simulated online platform. In order to establish a shared key between Alice and Bob in noised medium, the CASCADE protocol was applied to detect error correction for unmatched bits in the shared key. With this study, a test and interpretive environment was established for a method that requires high cost to be implemented in real environment.