Implementation Analysis of the PRESENT Algorithm on ATmega328P for Securing RFM95W LoRa Communications

Long Range (LoRa) technology is widely used, for example in industry, smart cities, agriculture, transportation, and the Internet of Things (IoT). However, LoRa communications that do not have an encryption algorithm implemented are not secure, and it is possible that data can be intercepted and read by hackers. It is necessary to apply cryptography to the LoRa system to keep the confidentiality of data when transmitted. LoRa systems are generally hardware with limited computing resources and power, for example, the LoRa system has an ATmega328P 8-bit microcontroller. A lightweight cryptographic algorithm, such as the PRESENT algorithm, is required to be applied to LoRa system hardware with low computational resources. In this research, we analyze the implementation of the PRESENT algorithm on the ATmega328P to secure LoRa RFM95W communications. The research method in this research consists of the following stages: literature study, design, implementation, testing, and analysis. Based on the test vector, this research successfully implemented the PRESENT algorithm to secure data transmitted via LoRa RFM95W communication. There are three scenarios in the testing stage with the results: In scenario a, LoRa Tx uses $\mathbf{1 1 \%}$ of the program storage space, and LoRa Rx uses $12 \%$; in scenario b, LoRa Tx uses $19 \%$ of the program storage space, and LoRa Rx uses $33 \%$; and in scenario c, LoRa Tx uses $59 \%$ of the program storage space, and LoRa Rx uses 72%. The remaining LoRa program storage space with the PRESENT algorithm implementation (in scenario b) can be used to implement other use cases, for example, secure RFM95W LoRa communications implemented in various fields.