# Risk Assessment of UAV Cyber Range Based on Bayesian-Nash Equilibrium
## 6 Application and Analysis
According to the cost of defense strategies, the impact of the UAV range and the experience of managers, defender strategies can also be divided into two categories, represented by \(t_{D}\) = [high level defender, low level defender], and the specific information is shown in Table 4.  
According to the action strategies adopted by both attack and defense, the attack-defense tree of the UAV cyber range is constructed. The following is an example of the attack-defense tree as shown in Figure 4, aiming at the two kinds of attack events that the ground station and the UAV communication system may suffer. \begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline \multirow{2}{*}{**Classification**} & \multirow{2}{*}{**Base Attack**} & \multirow{2}{*}{**Description**} & \multicolumn{2}{c}{**Adventurous Attacker**} & \multicolumn{2}{c}{**Conservative Attacker**} \\ \cline{5-6}  & & & \(b_{1}^{A}\) & \(b_{2}^{A}\) & \(b_{3}^{A}\) & \(b_{4}^{A}\) \\ \hline \multirow{6}{*}{Root} & \(a_{1}\) & UAV model, operating system, communication protocol and other collection & \(\blacksquare\) & & \\ \cline{2-6}  & \(a_{2}\) & Using radio-jamming equipment to block the UAV’s communication with the ground station & \(\blacksquare\) & & \\ \cline{2-6}  & \(a_{3}\) & Exploit known vulnerabilities in UAV software to gain initial access & \(\blacksquare\) & & \\ \hline \multirow{6}{*}{User} & \(a_{4}\) & By exploiting the risk, the user’s permission is upgraded from the common user to the root user & \(\blacksquare\) \\ \cline{2-6}  & \(a_{5}\) & Tampering with a UAV’s mission data to influence its flight behavior & \(\blacksquare\) & \\ \cline{1-1} \cline{2-6}  & \(a_{6}\) & Building back doors into UAV system to maintain long-term control & \(\blacksquare\) & \\ \cline{1-1} \cline{2-6}  & \(a_{7}\) & Building back doors into UAV system to maintain long-term control & \(\blacksquare\) & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Description of attacker actions. Figure 3: UAV communication topology. The defense benefits and attack benefits are calculated based on that shown in 3.2. In the attack-defense tree, if it is able to resist and attack events at the same time, the current analysis of the situation is that attack events may be initiated by adventurous attackers, but may also be initiated by conservative attackers, and unmanned aerial range information security managers can not accurately judge which is the case. Therefore, it is necessary to calculate the respective benefits of both sides when the defender faces the adventurous attacker and the conservative attacker. Tables 5-8 list the calculation results. \begin{table}
\begin{tabular}{l l l l l l} \hline \hline \multirow{2}{*}{**Defensive Strategy**} & \multicolumn{2}{c}{**High Defender**} & \multicolumn{2}{c}{**Junior Defender**} \\ \cline{2-6}  & \(b_{1}^{D}\) & \(b_{2}^{D}\) & \(b_{3}^{D}\) & \(b_{4}^{D}\) \\ \hline Information protection & \(\blacksquare\) & & & \\ Communication encryption & & & & \\ Update regularly & \(\blacksquare\) & & & \(\blacksquare\) \\ Authority management & & & & & \\ Data integrity check & & & & & \\ Malware protection & & & & & \\ Data encryption & & & & & \\ Control system hardening & & & & & \\ Cyber monitoring & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Description of defender actions. Figure 4: An example of an attack–defense tree at a UAV range.