Quantum key distribution with polarized qubits has not yet been realized over the aerial fiber, due to rapid polarization changes. Here, we report our recent work towards quantum communication through an aerial fiber channel. We designed a fast polarization feedback module featuring high efficiency, fast speed, and good stability. With this module, we implemented long-distance quantum key distribution over different types of aerial fiber links based on polarization encoding. Our work takes a significant step towards the application of quantum communications in complex environments.

Quantum key distribution (QKD) promises to deliver secure keys, which can be applied for security demands in optical networks by using cost-efficient and scalable lightpaths. To achieve such secure communication, the QKD integrated with optical networks has become a promising scenario to provide key provisioning services in optical networks. As an inevitable problem, the occurrence of failures becomes a challenge for the resiliency of the network. In that context, this paper studies the resilient QKDintegrated optical networks against single link failure. By analyzing and quantifying the key provisioning services, we constructed the secret-key flow model (SKFM) for the failure-affected and failure-unaffected cases. Based on the SKFM, a secret-key recovery strategy (SKRS) including three algorithms (i.e., onepath recovery method (OPRM), multi-path recovery method (MPRM), and time window-based recovery method (TWRM)) is designed to recover failure-affected key provisioning services in the network. The simulation work has been conducted to evaluate the performance of OPRM, MPRM, and TWRM in terms of key-service recovery ratio, secret-key recovery ratio, wavelength consumption ratio, and secretkey consumption ratio. Numerical results show that the three algorithms can recover failure-affected key provisioning services effectively, i.e., the MPRM outperforms the OPRM and the TWRM outperforms the MPRM. Better recovery can be realized by sacrificing more wavelength and secret-key resources, which are also required for the delivery of the QKD in the network. Thus, a trade-off can be achieved between the recovery of key provisioning services and the delivery of the QKD on wavelength resources and secret-key resources.

With the access of massive terminals in the power Internet of things (IoT), the efficiency of information sharing is improved, but the grid boundary is increasingly blurred. The traditional centralized security management mode is facing a severe security situation, which is difficult to meet the high security requirements of the system operation. There are three main risks: 1) the execution authority of control information is not strictly controlled at the equipment level; 2) Data and authority are not separated, which makes the security management of data layer have hidden dangers; 3) Power supply chain is faced with the problems of data island, data trust and performance guarantee. Based on the characteristics of blockchain technology (BcT), such as non-tampering, collective maintenance and transaction non repudiation, this paper constructs a data protection architecture covering device layer, data layer and business layer, realizes high-level security protection of data flow in all links of power network, and improves the security management and control ability of the system. Through the scheme proposed in this paper, the implementation of control information is strictly managed, the use rights management of data is more standardized, and the credibility and interaction rate of business data are greatly improved.

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