# Study About the Performance of Ascon in Arduino Devices
## 6 Conclusions  
In this work, we have presented the mathematical background, specifications, security foundations, and properties of the Ascon cipher suite, the winner of the Lightweight Cryptography standardization process organized by NIST. After that, we considered an exhaustive study about the Ascon performance on four Arduino devices, namely Arduino DUE, Arduino Mega2560, Arduino Nano Every, and Arduino Nano EPS32. Finally, we have carried out a comparison of the mentioned implementations. For the four Arduino devices and for the three Ascon versions, the number of cycles and the number of encryption and decryption operations for the processes of encryption and decryption are similar for each period of time considered. In addition, for all Arduino devices, the Ascon-128a version presents the lowest values in relation to the number of cycles, on average, whereas the Ascon-80 pq version has the biggest values. In contrast, the performance of the Arduino DUE and Arduino Nano ESP32 are quite different from the other two devices. As it is shown in Tables 5, 6, 11, and 12, both devices consume a significantly higher number of clock cycles, on average, and they are capable of performing a much greater number of encryption and decryption operations within the same time period. This higher performance of both devices can be attributed to the more powerful hardware of the DUE and the Nano ESP32. They have 32-bit microcontrollers that provide significantly more computational power and efficiency in handling cryptographic tasks compared to the ATmega2560 processor of the Mega2560 and the more limited resources of the Nano Every. Furthermore, the more powerful processor and larger memory capacity of the Arduino Nano ESP32 play a crucial role in its performance. These features allow for better data handling and the faster execution of all algorithms, especially compared to the other three devices with slower processors or less available memory. This means that the Arduino Nano ESP32 can handle larger datasets or perform cryptographic operations more smoothly without running into memory bottlenecks that affect other devices. We have also analyzed an implementation of AES-128 on three of the four devices considered in order to compare the results obtained of the Ascon family with another of the standard algorithms which is sometimes used in IoT environments. It has not been possible to use the Arduino Nano Every with AES-128 because this device is not able to support the implementation of AES-128. From the results obtained, we can state that the three versions of Ascon have a better performance than AES-128 on the Arduino DUE, with the Ascon-128a being the fastest version for this device. However, AES-128 is significantly more efficient than any of the Ascon versions on the Arduino Mega2560. Finally, it should be noticed that the behavior of the three versions of Ascon and AES-128 on the Arduino Nano ESP32 are quite similar, although the algorithm that offers the lowest performance is AES-128, with Ascon 128a being slightly better. In summary, in the present work we extended a previous work considering different devices and analyzing the efficiency of all versions of the Ascon family in order to have data that allow us to choose, for different use cases, which device an algorithm is more suitable, according to the restrictions imposed by the system to be used. In particular, the obtained results can be of interest for some use cases, for example, a relevant use case could be quantum key distribution in free space with drones, where the ability to operate on resource-constrained hardware is essential. In particular, the Ascon-80 pq, which is quantum-resistant, is interesting in the process of an agile transition towards being quantum-resistant. Conceptualization, V.S.L., L.H.-A. and L.H.E. ; methodology, L.H.-A. and A.Q.-D.; software, V.S.L., L.H.-A. and J.I.S.G. ; validation, V.S.L., L.H.-A., L.H.E., J.I.S.G. and A.Q.-D.; formal analysis, L.H.-A., L.H.E. and J.I.S.G. ; investigation, V.S.L., L.H.-A. and L.H.E.