Lightweight Cipher Aware Countermeasure Using Random Number Masks and Its Evaluation

Recent advancements in the Internet of Things (IoT) technology has left built-in devices vulnerable to interference from external networks. Power analysis attacks against cryptographic circuits are of particular concern, as they operate by illegally analyzing confidential information via power consumption of a cryptographic circuit. In response to these threats, many researchers have turned to lightweight ciphers, which can be embedded in small-scale circuits, coupled with countermeasures to increase built-in device security, even against power analysis attacks. However, while researchers have examined the efficacy of embedding lightweight ciphers in circuits, neither cost nor tamper resistance have been considered in detail. To use lightweight ciphers and improve tamper resistance in the future, it is necessary to investigate the relationship between the cost of embedding a lightweight cipher with a countermeasure against power analysis in a circuit and the tamper resistance of the cipher. Accordingly, the present study determined the tamper resistance of TWINE, a typical lightweight cipher, both with and without a countermeasure; costs were calculated for embedding the cipher with and without a countermeasure as well.