## 6 Conclusions  
In this paper, the AES encryption algorithm and a preprocessing mechanism (Pre) were combined to optimize the efficiency of data communication, and the effectiveness of the scheme was verified by comparing and analyzing the performance of different encryption schemes. The experimental results showed that compared with the traditional AES encryption scheme, the AES+Pre scheme reduced the average transmission delay by 49.1%, improved the throughput by 96.4%, and reached an acceleration ratio of 1.96. At the same time, the AES+Pre achieved a good balance between transmission efficiency and implementation complexity compared with other mainstream encryption schemes (ECC and RSA), which is especially suitable for large-scale data transmission scenarios. AES+Pre performed well in data security and communication efficiency for information transmission of smart devices in ports. In terms of data security improvement, the AES encryption algorithm provided efficient data encryption and decryption capabilities, and the preprocessing mechanism further optimized the key algorithm steps so as to significantly improve the speed of encrypted transmission while ensuring data confidentiality and integrity. In terms of communication efficiency, the AES+Pre meets the needs of high-frequency and large-scale data transmission in the port environment by reducing the average transmission delay and improving the throughput, and it provides efficient and reliable support for data exchange between smart devices in the port.  
However, the proposed scheme still needs to be further optimized in some application scenarios. For example, in the experiment, a 16-core AMD Ryzen 76800H processor was used. Its multi-core parallel processing ability and high clock frequency have a direct effect on data encryption and transmission efficiency, but the performance bottleneck that may occur in the environment of low-performance hardware (such as single-core or low-frequency processors) needs to be considered. Future studies can simulate low-performance processor environments to verify whether the performance of the proposed scheme is still advantageous when hardware capabilities are limited. In addition, the ECC performs well in some low-latency scenarios, but the AES+Pre is more suitable for large data volume transmission scenarios. Therefore, in future research, the selection of communication protocols can be further optimized according to the requirements of different transmission scenarios, and the balance between low delay and high throughput can be explored to meet the needs of a wider range of intelligent port applications.  
The authors confirm the contributions to the paper as follows: study conception and design: Z.X. and A.L.; validation, X.Y.; data collection: Z.X. and S.H.; analysis and interpretation of results: A.L. and S.H.; draft manuscript preparation: Z.X. and Y.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China, grant number 61972334.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
We thank [PERSON] for providing assistance.  
Author [PERSON] was employed by the company No. 9 Branch Company of Qinhuangdao Port Co., Ltd. The remaining authors declare that the re-search was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.