An Efficient and Provably Secure SM2 Key-Insulated Signature Scheme for Industrial Internet of Things

With the continuous expansion of the Industrial Internet of Things (IIoT), more and more organisations are placing large amounts of data in the cloud to reduce overheads. However, the channel between cloud servers and smart equipment is not trustworthy, so the issue of data authenticity needs to be addressed. The SM2 digital signature algorithm can provide an authentication mechanism for data to solve such problems. Unfortunately, it still suffers from the problem of key exposure. In order to address this concern, this study first introduces a key-insulated scheme, SM2-KI-SIGN, based on the SM2 algorithm. This scheme boasts strong key insulation and secure key -updates. Our scheme uses the elliptic curve algorithm, which is not only more efficient but also more suitable for IIoT-cloud environments. Finally, the security proof of SM2-KI-SIGN is given under the Elliptic Curve Discrete Logarithm (ECDL) assumption in the random oracle.