Quantum key distribution over FSO channel using error reconciliation protocol

Quantum key distribution (QKD) has evolved as a robust way of secret key distribution based on renowned modern physics concepts. To transmit sensitive information in the government, private, and personal sectors, high-security levels are now necessary. All conventional cryptographic algorithms applied in the communication models, which rely on mathematical models and conceptual assumptions, are unsecure. Thus, QKD systems are the best choice for protecting this information as a countermeasure since they provide unconditional security. In this paper, a design is proposed for the FSO channel using the CASCADE protocol under different atmospheric condition such as haze, rain and snow. The suggested framework's effectiveness and security in the context of QKD with two non-orthogonal photon states are assessed. Simulation results of this model show the percentage of original sequence recovery; the number of errors removed, optical spectrum at transmitter and receiver for a base frame length of 10(4) bits. Moreover, Error correction is calculated per iteration to improve signal quality at the receiver side and compared to previous work. The calculated value in this article shows a better result. Hence, both the sender and the receiver could achieve a security key using this method.