IoT Device Friendly Leveled Homomorphic Encryption Protocols

Leveled homomorphic encryption (LHE) is important because it enables calculations on encrypted data. Are there any weaknesses of LHEƒ The answer is yes. The LHE process is too heavy. If analyzers attempt to collect data from IoT devices and use them safely; this is a significant challenge because IoT devices have low performance. First, the load should be clarified in this study when using LHE with smartphones, which are high-performance IoT devices, and Raspberry Pi, an IoT device with lower performance than smartphones. Next, we tackle the system design of an LHE that does not burden IoT devices. Changing the LHE algorithm or performing hardware optimization in the proposed method is needless. We implemented three LHE systems, including the proposed method, and evaluated the most suitable for IoT devices. We demonstrated that the proposed method is 31 - 91 times faster than the existing methods for plaintext encryption on smartphones.