# Modeling and Performance Analysis of Satellite Network Moving Target Defense System with Petri Nets
## 7 Conclusions  
This paper focuses on the performance evaluation of satellite networks with active defense technology. SPN is used to build performance evaluation models of satellite networks. Then, we theoretically inferred and analyzed the proposed SPN models. After that, we conduct extensive simulations on the PIPE platform, and the influence of different parameters of the active defense technique on the performance of the whole satellite network is evaluated. The conclusions are as follows: the deployment of MTD technology reduces the overall performance of the satellite network. Change frequency is the key factor to the performance loss and security of the entire satellite network. To maintain the balance of performance-security, the trade-off between communication performance and change frequency will be one of the main points of research on active defense technology. Improving synchronization and migration efficiency, link anti-interference, and transmission capacity, as well as satellite processing service capacity can effectively alleviate this problem. The results we get can be used for further improvement of active defense technologies, as well as for the design and optimization of satellite network moving target defense systems. All authors contributed to the development and completion of this paper. Conceptualization and project administration, L.S. ; Methodology validation, formal analysis, and writing--original draft preparation, S.D. ; writing--review and editing, Y.M. ; visualization, S.L. All authors have read and agreed to the published version of the manuscript. This research was funded by the Shandong Provincial Natural Science Foundation under Project ZR2019 MF034, in part by the Research Funds from Guangxi Key Laboratory of Cryptography and Information Security under Grant GCIS201811, in part by the National Natural Science Foundation of China (NSFC) under Grant No. 61772551. Not applicable. All data included in this study are available upon request by contact with the corresponding author. The authors thank anonymous reviewers who gave valuable suggestions and useful comments, which will greatly improve the manuscript. The authors would also like to acknowledge the cooperation and invaluable assistance of the whole research team throughout the preparation of the original manuscript. The authors declare no conflict of interest. The following abbreviations are used in this manuscript:  
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