Abstract: The message queuing telemetry transport (MQTT) protocol is widely used for data transmission in earthquake early warning, rapid reporting, and disaster assessment due to its high concurrency and low latency. However, the protocol suffers from security vulnerabilities such as simplistic authentication, plaintext transmission, and susceptibility to message tampering. Moreover, existing security solutions struggle to simultaneously meet the requirements of lightweight design, compatibility with domestic innovation ecosystems, and multi-terminal security protection, which restricts its application in high-security earthquake-related operations. To address these issues, this study proposes a domestic cryptographic-enhanced MQTT secure transmission scheme tailored for domestic innovation ecosystems. Based on the enhanced authentication mechanism of MQTT 5.0, the scheme designs a domestic cryptographic-enhanced authentication algorithm. Utilizing SM2 encryption and digital signature technology, it enables bidirectional trusted authentication between the client and the broker in just four rounds of interaction, achieving a balance between security and lightweight performance. Additionally, a key re-encryption mechanism is introduced to establish a "one-key-per-subscriber" protection model, effectively mitigating the risk of key leakage in multi-subscriber scenarios caused by the "single-topic-single-key" approach. Security analysis confirms that the scheme can resist typical attacks such as identity forgery, man-in-the-middle interception, and tampering. Simulation results show that in 25 repeated tests, the average time for identity authentication is 13.36 ms, the average time for topic key acquisitionis 0.977 ms, and the average data transmission time in scenarios with 300 subscribers is 551.78 ms. Constructed with domestic cryptographic algorithms, this scheme is compatible with domestic innovation ecosystems and low-computing-power devices such as earthquake early warning terminals, fully meeting the core requirements of high security and low latency for earthquake-related data transmission.

Key words: message queuing telemetry transport (MQTT), Chinese commercial cryptographic algorithm, information security, information innovation environment