SCDP: Smart Contract-based Decentralized Privacy System for Securing Data Ownership Management

Secure data ownership management is significant for realizing personal and private data sharing, which can be widely used with consumer electronics. The notion of the decentralized privacy (DP) is introduced by Zyskind et al., and accordingly the first DP system is implemented through blockchain and off-blockchain distributed hashtable. To address the efficiency and overhead issues, we present a conceptually simple solution directly from smart contracts with cryptographic primitives. Our system is called the smart contract-based decentralized privacy (SCDP) system. We propose the basic SCDP system as a warm-up to introduce the design principle based on symmetric encryption. Moreover, the strong SCDP system is provided by using ciphertext-policy attribute-based encryption for supporting more flexible scenarios of access control and also eliminating some limitations of the basic system.