# Trustworthiness of Situational Awareness: Significance and Quantification
## 5 Numerical Results
### Case 1: High-Trust Information Source
that affect the trustworthiness of a link. In the following, we calculate the scores of these metrics for this case. _Confidentiality:_ Since the UAV encrypts the information to be sent, and this encrypted information traverses through the radio link between the UAV and GCS, the confidentiality score for \(l_{1}\) or \(l_{UAV-GCS}\) can be assigned as \(1\). _Integrity:_ Since the HMAC of the message is transmitted along with the message in this case, \(l_{1}\) can be ascribed an integrity score of \(1\). _Availability:_ Assuming that the radio link can carry the messages and is not overloaded with data traffic nor is affected by any denial-of-service attack, an availability score of \(1\) can be attributed to \(l_{1}\). _Quality:_ Here, the quality of a link can be referred to as its bit error rate. Assuming a bit error rate of \(5\times 10^{-3}\)[19], the quality score for \(l_{1}\) can be calculated as 0.995 (i.e., \(1-0.005\)). Since, in our model, there are four metrics that influence the trustability of a link, we assign a weight of \(0.25\) (i.e., \(1/4=0.25\)) to each metric, although different weights can be assigned depending on mission needs. Using Equation (4), the trustworthiness score of the links \(l_{1}\) or \(l_{UAV-GCS}\) can be determined as \(\mathcal{T}_{l_{1}}=(0.25)(1)+(0.25)(1)+(0.25)(1)+(0.25)(0.995)=0.99875\). **Link \(l_{2}\) or \(l_{GCS-GN}\):** Here, we calculate the trustworthiness of the wired link \(l_{2}\) or \(l_{GCS-GN}\) between the GCS and the GN that connects the GCS to the core network based on Equation (4). In the following, we calculate the score of the metrics that affect the trustworthiness of the link for this case. _Confidentiality:_ Since the encrypted information traverses the wired link between the GCS and the GN, \(l_{2}\) or \(l_{GCS-GN}\) can be assigned a confidentiality score of \(1\). _Integrity:_ Since the HMAC of the message is transmitted along with the message on the link \(l_{2}\) in this case, the integrity score for \(l_{2}\) can be ascribed as \(1\). _Availability:_ Assuming that the link can carry the messages and is not overloaded with data traffic nor is affected by any denial-of-service attack, an availability score of \(1\) can be attributed to \(l_{2}\). _Quality:_ Assuming a bit error rate of \(48\times 10^{-5}\)[20], the quality score for \(l_{2}\) can be calculated as \(1-0.00048=0.99952\). Since, in our model, there are four metrics that influence the trustability of a link, we assign a weight of \(0.25\) (i.e., \(1/4=0.25\)) to each metric, although different weights can be assigned depending on mission needs. Using Equation (4), the trustworthiness score of the link \(l_{2}\) or \(l_{GCS-GN}\) can be determined as \(\mathcal{T}_{l_{2}}=(0.25)(1)+(0.25)(1)+(0.25)(1)+(0.25)(0.99952)=0.99988\). **Link \(l_{3}\) or \(l_{GN-RN}\):** The trustworthiness of the wired link \(l_{3}\) or \(l_{GN-RN}\) between the GN and the RN in the core network can be calculated similarly to the wired link \(l_{2}\), and can be given as \(\mathcal{T}_{l_{3}}=(0.25)(1)+(0.25)(1)+(0.25)(1)+(0.25)(0.99952)=0.99988\). **Link \(l_{4}\) or \(l_{RN-DFN}\):** The trustworthiness of the wired link \(l_{4}\) or \(l_{RN-DFN}\) between the RN and the DFN can be calculated similarly to the wired link \(l_{2}\), and can be given as \(\mathcal{T}_{l_{4}}=(0.25)(1)+(0.25)(1)+(0.25)(1)+(0.25)(0.99952)=0.99988\). **Link \(l_{5}\) or \(l_{DFN-CBN}\):** The trustworthiness of the wired link \(l_{5}\) or \(l_{DFN-CBN}\) between the DFN and the CBN can be calculated similarly to the wired link \(l_{2}\), and can be given as \(\mathcal{T}_{l_{5}}=(0.25)(1)+(0.25)(1)+(0.25)(1)+(0.25)(0.99952)=0.99988\).