## 6 Conclusions  
Addressing and managing the risks associated with security incidents and physical damage has become critical, as our world applies more intelligent environments. We integrated a private blockchain and the PUF function to ensure suitable drone registration in the IoD systems. During the design, we paid attention to the scalability issue and effectively stored the keys on the ARP table. We also considered that the exchanged keys should be stored securely on the devices, and we assumed that the table's data are encrypted by the PUF key of the device. We used the exchanged symmetric key to provide authentication and confidentiality between the drone-to-drone and drone-to-base station  
\begin{table}
\begin{tabular}{l l l l l l l} \hline \hline
**Standpoint** & **LoRa** & **Bluetooth** & **BLE 5 Long** & **Wi-Fi** & **(2.4** & **Cellular** \\  & & & **Range** & **GHz)** & & **(4G)** \\ \hline Range & 5–10 km & 50–100 m & 400–1000 m & 45–75 m & 600–40,000 m \\ \hline Affordability & EUR 7–EUR & built-in or EUR 5–8 per module & built-in or EUR 20 per module & built-in or EUR 5–EUR 20 per module & built-in or EUR 3–EUR 50 per module & EUR 20–module & EUR 50 per module \\ \hline Maximum & 22 kbps & 2 Mbps & 2 Mbps & 72–600 Mbps (802.11n) & 4–12 Mbps are common \\ Data Rate & & & & & & \\ \hline \hline \end{tabular}
\end{table}
Table 8: LoRa comparison to other technologies.  
communications. For our application, we found that LoRa is an appropriate physical layer due to its long range, low power consumption, interference-resistant properties, and acceptable data rate. Our prototype tests proved that LoRa is a reliable physical layer that can support communication among multiple network participants at the same time. Additionally, our security analysis using ProVerif showed that attackers cannot access the exchanged key, and mutual authentication, key freshness, and key confirmation were also provided. In addition to the formal security analysis, we also aimed to informally examine the impact of some other drone-related attacks. We compared the communication and storage costs to solutions mentioned in the related literature for the practical aspects. The field of the Internet of Drones will face many challenges in the future, both from regulatory and technical points of view. These problems include privacy issues related to the data collected by drones, swarm management issues, the impact of artificial intelligence on drones, and many other topics.  
Conceptualization, N.O. and A.H.; Software, B.M.; Formal analysis, N.O. and A.H. All authors have read and agreed to the published version of the manuscript.  
The presented research has been supported by the project no. 101083965--DigitalTech EDIH--DIGITAL-2021-EDIH--01 that has been implemented with the support provided from the European Union, co-funded by the European Commission's Digital Europe Programme, financed under the DIGITAL-2021-EDIH funding scheme. The research was supported by the Ministry of Culture and Innovation NRDI Office within the framework of the Infocommunication and Information Technology National Laboratory Program.  
Prototype GitHub Link. Available online: [[https://github.com/Gepsonka/TDK](https://github.com/Gepsonka/TDK)]([https://github.com/Gepsonka/TDK](https://github.com/Gepsonka/TDK)) (accessed on 1 January 2023).  
The authors declare no conflict of interest.