Taming energy cost of disk encryption software on data-intensive mobile devices

Disk encryption software is frequently used to secure confidential data on mobile devices. However, it is notoriously challenging for disk encryption software to ensure its security in cryptography without involving significant energy overhead. To address the challenge, we design a both cryptographically secure and energy-efficient disk encryption software for mobile devices, Populus. On the one hand, Populus uses modular linear algebra and one-time pad technique to encrypt/decrypt sensitive data on mobile devices, thus ensuring its security in cryptograph. To illustrate, we prove Populus's semantic security. On the other hand, Populus is based on client–server pattern. Its client side works on the kernel layer of mobile devices powered by batteries, while its server side works on the application layer of computing devices powered by fixed electric power source. The server side helps the client side do the computation tasks unrelated to plaintext/ciphertext in the encryption/decryption process, therefore, the energy cost on mobile devices significantly declines. To demonstrate, we conduct energy consumption experiments on Populus and dm-crypt, a famous disk encryption software for Android and Linux mobile devices. The experimental results show that Populus consumes 50%–70% less energy than dm-crypt.