system to enter engineering deployment, the development of Quantum Key expansion trend in the medium to long term. In 2025, the global Quantum to grow to about $1.371 billion by 2030, with a Compound Annual Growth Rate (CAGR) of approximately 6.7% during the period from 2025 to 2030. Over a longer-term horizon, as quantum secure networks gradually transition from pilot projects to regionalized and networked deployment, the approximately $4.185 billion by 2035, with a CAGR of about 25% during the 2030-2035 period. Overall, the growth pace of the QKD market is highly correlated with the investment cycles of communication infrastructure. Its