## 6 Conclusions and Future Research  
With the advancement of automotive technology, various systems have been mounted on vehicles for user convenience. At the same time, the number of external contact points at which the vehicle can be accessed has increased. This means that the number of attack points at which attackers can attack vehicles has increased. The importance of vehicle cybersecurity has increased, since vehicle attacks can directly impact drivers, surrounding vehicles, and people. UNECE WP.29 and ISO/SAE 21434 recommend the application of cybersecurity elements to vehicles. After applying security elements, various security tests are needed to verify whether the system is fully operating and whether there are any errors. However, there are time, cost, and safety issues when performing tests in a real-world environment. Hence, simulations are used to perform various tests in advance, but there are difficulties in performing some tests because they are far from the real-world environment. Furthermore, we need a method of evaluating whether the security technology has been applied at the application level, rather than conformity testing, for processing misbehavior.  
In this study, we described a test platform that linked a virtual machine and the simulation equipment to overcome the limitations of conventional simulations. We also listed the methods of using the actual test platform using four security evaluation scenarios. Using the test platform proposed in this paper, one can secure time, cost efficiency, and safety. Furthermore, results can be obtained with various tests, since security threats and misbehaviors in the real-world environment can be tested. Data collection, analysis, and misbehavior detection of IDS can be performed without being constrained by programming languages, since the data generated by the simulation equipment can be processed from the outside.  
In the future, we plan to research to develop additional scenarios besides the four security evaluation scenarios used in this paper. Here, each scenario will be created more specifically to create practical scenarios for security evaluation. Currently, the research focuses on V2V, but we plan to develop test cases for various security threats that may occur in the Security Credential Management System (SCMS) and vehicle driving scenarios, as well as messages used for V2X, such as SPaT and MAP messages.  
Conceptualization, D.-H.L. and C.-M.K.; methodology, D.-H.L., H.-S.S,Y.-H.L. and W.-S.C.; software, C.-M.K.; validation, D.-H.L. and W.-S.C.; formal analysis, H.-S.S, investigation, D.-H.L. and C.-M.K.; resources, H.-S.S, Y.-H.L. and W.-S.C.; data curation, D.-H.L.; writing--original draft preparation, C.-M.K.; writing--review and editing, D.-H.L.; visualization, D.-H.L. and C.-M.K.; supervision, D.-H.L. and W.-S.C.; project administration, H.-S.S. and Y.-H.L. All authors have read and agreed to the published version of the manuscript.  
This work was supported by Institute of Information & communications Technology Planning & Evaluation (IITP) grant funded by the Korea government (MSIT) (No. 2019-0-00148, Development of Dual Convergence Security Technology on Touch Control System using Smartphone for the control of Autonomous Driving Vehicle).  
Not applicable.  
Figure 17: The verification node checks the signer type of the BSM sent by the evaluation target node. When an event occurs, the signer type must be “certificate”. If it is “digest”, the verdict is “fail”. The figure on the left shows an event occurred but the signer type is “digest”, and the result is “fail”. The figure on the right shows that the signer type is “certificate” when an event occurs, and the result is “pass”.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Not applicable.  
**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.