Trusted Data Management for E-learning System Based on Blockchain

During the epidemic outbreak of COVID-19, all universities, middle schools and primary schools in China adopted the form of online teaching. It brings convenience, but it also raises some security and privacy issues. The challenge to solve the issues is how to achieve effective access control and how to ensure the authenticity of online data. Because blockchain has the characteristics of openness, unforgeability and decentralization, we present a trusted data management scheme for e-learning system based on blockchain. In the scheme, large amounts of resource data are stored in a distributed storage system; the evidences of uploaded data are stored in blockchain network established by high credible institutions. Once the data in the distributed storage are tampered, it will be discovered by looking up blockchain transactions. In order to make up for the lack of privacy protection in blockchain, we adopt attribute encryption. For different resources, different ciphertext policies are given. Only the users whose attributes satisfy the policy can decrypt the data. Further, a fine-grained access control scheme for e-learning is designed. In addition, the scheme can prevent collusion attacks; even if multiple users collude, they will not get more resources.