ABSTRACT Digital signatures provide scalable authentication with non‐repudiation and are vital tools for the Internet of Things (IoT). Many IoT applications harbor vast quantities of resource‐limited devices often used with cloud services. However, key compromises (e.g., physical, malware) pose a significant threat to IoTs due to increased attack vectors and open operational environments. Forward security and distributed key management are critical breach‐resilient countermeasures to mitigate such threats. Yet forward‐secure signatures are exorbitantly costly for low‐end IoTs, while cloud‐assisted approaches suffer from centrality or non‐colluding semi‐honest servers. In this work, we create two novel digital signatures called Lightweight and Resilient Signatures with Hardware Assistance ( LRSHA ) and its Forward‐secure version ( FLRSHA ). They offer a near‐optimally efficient signing with small keys and signature sizes. We synergize various design strategies, such as commitment separation to eliminate costly signing operations and hardware‐assisted distributed servers to enable breach‐resilient verification. Our schemes achieve magnitudes of faster forward‐secure signing and compact key/signature sizes without suffering from strong security assumptions (non‐colluding, central servers) or a heavy burden on the verifier (extreme storage, computation). We formally prove the security of our schemes and validate their performance with full‐fledged open‐source implementations on both commodity hardware and 8‐bit AVR microcontrollers.
Nouma et al. (Thu,) studied this question.