Abstract:

To address security problems existing in data trading schemes such as the key leakage problem, and the collusion problem, an atomic and accountable data trading scheme is proposed. It uses an automatic payment mechanism that combines data auditing technology and smart contracts to ensure data integrity and fairness payment for the trading process. By using the self-certified public keys to design the user registration process, the user's private key is still safe even if it suffers from a single point of failure. In the meanwhile, with the help of the session key to encrypt communication, which solves the problem of symmetric key distribution while efficiently maintains communication security. An accountability mechanism is constructed to implement public auditing to handle user disputes, which resists the collusion attacks. The security analysis and simulation results show that the scheme can not only resist the key leakage attacks and the collusion attacks, but also reduce communication costs and perform accountability efficiently.

Key words: data integrity, data sharing, accountability, key reconstruction, smart contract