Efficient Certificateless Online/Offline Signcryption Scheme for Edge IoT Devices

The emergence of edge computing brings data processing and storage to the vicinity of terminal equipment, which can quickly respond to user needs and reduce the computational burden of the traditional centralized cloud computing model, resulting in a model of edge computing-assisted cloud computing. In this architecture, how to prevent other untrusted entities from leaking user privacy has become one of the most critical concerns. To address this concern, many cryptographic schemes supporting the traditional cloud model to protect the data security sharing of IoT devices have been proposed. However, resource-constrained devices are an essential component of the Internet of Things (IoT). Its characteristics are one of the main reasons that affect the efficiency of schemes, and traditional cryptographic schemes are not suitable for edge computing. Therefore, in order to ensure secure data sharing between IoT devices, we come up with an improved certificateless online/offline signcryption (CLOOSC) scheme and achieve lower computational overhead, when offline calculation is not considered, the resource-constrained IoT device under the cloud-edge collaboration architecture requires only one point multiplication, while only one bilinear pairing is required in the verification phase. In the random oracle model, our scheme is proved to be IND-CCA2 secure. The experiment results show our scheme can be lightweight in terms of time cost.