At present, the degree of correlation between various types of data in backbone communication networks is low, and there is no automatic calculation and correlation function between data and data. Faced with a large amount of feedback data on power grid operation, it is difficult to automatically associate defects, regulations, contingency plans, real-time data, and equipment attribute data, and there is a lack of effective application and sharing methods for troubleshooting knowledge. The perception of important business channel faults, analysis of business overload links, and troubleshooting and disposal of fault points rely heavily on manual judgment, requiring manual retrieval of relevant information from different systems. Due to the varying problem-solving abilities of employees and the lack of experience and knowledge accumulation, it is difficult to guarantee the processing time of on-site faults. To address the above issues, research on fault diagnosis and inference technology for backbone optical communication systems based on knowledge graphs will be carried out. A knowledge graph will be established for the correlation of operational faults between the large power grid and backbone optical communication systems, as well as a deduction and analysis model for the impact range of operational faults in backbone optical communication systems. A solution for early warning of operational risks and hidden dangers in backbone optical communication systems will be formed, providing effective support for improving the information and communication security capabilities of the power grid.