Design of Side-Channel-Resistant Electromagnetic Band-Gap on IoT Microcontroller

Abstract

To ensure the security of electronic devices and to meet the requirements for data confidentiality, integrity, and accessibility, systems often utilize a combination of cryptographic techniques and communication protocols. However, devices that employ encryption mechanisms are vulnerable to side-channel attacks (SCA), which could potentially allow unauthorized access to original data. Despite advancements in encryption algorithms, the challenge of safeguarding against key theft remains significant. Our proposed solution introduces a novel approach that uses periodic structure techniques, emphasizing a shielding design with electromagnetic band-gap (EBG) characteristics. This shielding is strategically positioned on IoT device microcontrollers to defend against SCA while maintaining message transmission within the 2.4 GHz Wi-Fi frequency range. Furthermore, we have established a comprehensive SCA system to validate the security of AES-128 encrypted transmissions. In scenarios where microcontrollers lack protective mechanisms, capturing fewer than 40 traces of encrypted signals can compromise the encryption key. However, our innovative EBG structure, designed to shield specific frequency bands, ensures that encryption keys are securely protected, even when subjected to analysis involving more than 20,000 signal traces.