Protection path and security-metric-based resource allocation algorithm in quantum key distribution optical networks

Quantum key distribution (QKD) optical networks can provide more secure communications. However, with the increase of the QKD path requests and key updates, network blocking problems will become severe. The blocking problems in the network can become more severe because each fiber link has limited resources (such as wavelengths and time slots). In addition, QKD optical networks are also affected by external disturbances such as data interception and eavesdropping, resulting in inefficient network communication. In this paper, we exploit the idea of protection path to enhance the anti-interference ability of QKD optical network. By introducing the concept of security metric, we propose a routing wavelength and time slot allocation algorithm (RWTA) based on protection path, which can lessen the blocking problem of QKD optical network. According to simulation analysis, the security-metric-based RWTA algorithm (SM-RWTA) proposed in this paper can substantially improve the success rate of security key (SK) update and significantly reduce the blocking rate of the network. It can also improve the utilization rate of resources such as wavelengths and time slots. Compared with the non-security-metric-based RWTA algorithm (NSM-RWTA), our algorithm is robust and can enhance the anti-interference ability and security of QKD optical networks.