# Trustworthiness of Situational Awareness: Significance and Quantification
## 5 Numerical Results
### Case 1: High-Trust Information Source  
Let us consider an ISR UAV that is equipped with various sensors, such as optical sensors and infrared sensors. The UAV either sends it sensed information or the result of its on-board analytics to the ground control station (GCS) through a radio link as depicted in Figure 3. The UAV encrypts the information sent to the GCS, and also concatenates a hash of the message to help detect any intrusion. The GCS sends the encrypted information to a gateway node (GN) through a wired link. The GN is connected to a router node (RN) through a wired link, which in turn is connected to a data fusion node (DFN) through a wired link. The DFN node is connected to the COP builder node (CBN) via a wired link. We note that the number of RNs and links between the GCS and the CBN depend on the distance between the GCS and the CBN, and can vary for different settings. Nevertheless, our illustration of the COP trustworthiness quantification (Figure 3) can be adapted for different settings. In the following, we first evaluate the trustworthiness of each source and device along the route from the source to the CBN (Figure 3). Afterwards, we evaluate the trustworthiness of links from the source to the CBN, and finally we evaluate the trustworthiness of the ISR UAV information at the CBN. **ISR UAV (SA Source):** We calculate the trustworthiness of the ISR UAV based on Equation (1) of our proposed model (Section 4.1). To obtain the trustworthiness of a source, we first need to obtain the score of various metrics (e.g., confidentiality, integrity, authenticity, etc.) stipulated in Equation (1) that affect the trustworthiness of the source. In the following, we calculate the score of these metrics for this case. _Confidentiality:_ For this case, the assumption is that the information gathered and analyzed by the UAV is stored in a secure memory, and is also encrypted using an advanced encryption standard (AES) or another encryption algorithm with a comparable security level. Consequently, the UAV for this case can be assigned a confidentiality score of 1. As a guideline, one can assign the highest scores (1 in this case) for security metrics, such as confidentiality, integrity, authenticity, etc., if the source employs algorithms and protocols standardized by the standardization bodies, such as the National Institute of Standards and Technology (NIST) [17]. _Integrity:_ For this case, the UAV employs error correction code (ECC) memory to detect and correct \(n\)-bit errors in memory, and also calculates the hash-based message authentication code (HMAC) of the message or information to be transmitted to the GCS. Hence, the UAV for this case can be assigned an integrity score of 1. _Authenticity:_ For this case, the UAV can be successfully authenticated with an authentication protocol (such as the protocol in [18]), and can be assigned an authenticity score of 1. _Availability:_ For this case, the UAV is responsive to the authentication and communication protocols' messages, and is available; hence, it can be assigned an availability score of 1. _Non-repudiability:_ Since the UAV encrypts the message with its secret key, which no other source possesses, the message can be associated with the UAV. In this case, public key infrastructure (PKI) is employed by the UAV; the UAV can also sign the message with its private key, which can be verified by the CBN using the public key of the UAV, thus unambiguously binding the message to the UAV. Since the UAV in this case employs these security mechanisms that ensure that the message originated from the UAV, it can be assigned a non-repudiability score of 1. _Precision:_ In this case, the UAV is performing on-board analytics on the sensed information, the precision can be assigned based on the average precision of the AI algorithm employed for tasks, such as classification, object detection, etc. The precision score depends on the precision of a particular model or algorithm employed by the UAV. For this numerical example, we assign a precision score of 0.96.