## 2 Traditional Encryption Techniques
### Security Vulnerabilities  
Traditional encryption algorithms, while widely used, possess vulnerabilities that can be exploited, especially in resource-constrained environments like UAVs operating in LEO settings.  
Brute-force attacks become a significant concern when key lengths are insufficient. For instance, using shorter keys for AES or RSA can weaken their resistance against exhaustive key search attempts [10]. The limited computational resources of UAVs can further exacerbate this risk, as they may lack the capacity for frequent key regeneration or complex countermeasures. Additionally, emerging quantum-assisted brute-force attackspose a long-term threat, potentially reducing the time needed to break traditional encryption keys. For example, [PERSON]'s algorithm theoretically reduces the effective key length of AES, highlighting the importance of considering quantum-resistant cryptographic methods. In LEO settings, where attackers may have increased opportunities to intercept data, the risk of such attacks is further amplified.  
Asymmetric cryptographic algorithms, such as RSA, are susceptible to third-channel attacks that exploit auxiliary information--such as energy consumption or the computation time--to extract private keys [11; 12]. Hardware-based countermeasures, including physically unclonable functions (PUFs), can significantly mitigate these vulnerabilities by generating unique hardware fingerprints. However, such solutions demand additional power and computational resources, which may reduce UAV flight times by up to 15%. This risk is particularly critical for UAVs, given their potential physical accessibility to attackers.  
The dynamic nature of communication channels in low Earth orbit (LEO) heightens the risk of data interception and manipulation. Environmental factors--including extreme temperatures and the inherent motion of UAVs--can compromise the performance of encryption systems. For example, high temperatures may alter UAV component behavior and expose side-channel leakages, while rapid movement can disrupt signal integrity, thereby providing opportunities for attackers to exploit retransmissions. Such vulnerabilities enable adversaries to intercept and modify transmitted data, which is especially concerning when the data govern UAV flight operations or contains critical agricultural production information. In UAV-based agricultural systems, data interception or manipulation may lead to the misclassification of crop health or delays in wildfire detection, ultimately resulting in economic losses and suboptimal disaster responses. In one simulated scenario, altered data streams induced a 30% delay in corrective actions for pest infestations, significantly reducing yield.  
In the context of UAVs used for agrotechnical monitoring, successful attacks could also result in the leakage of confidential data--such as information about crops, soil conditions, or UAV location--with potentially severe economic and environmental consequences. Table 1 provides a comparative analysis of the threats, vulnerabilities, mitigations, and challenges associated with UAV encryption.  
Figure 1: Impact of LEO conditions on traditional encryption methods.