Blockchain-based cross-user data shared auditing

In cloud storage, public auditing is a more popular data integrity verification technique since it allows users to delegate tasks fully trusted third-party auditor (TPA). However, difficult find such TPA in practical application. Besides, the centralised model makes have bear burdensome work pressure, which limits practicability of existing schemes. this paper, we firstly proposed blockchain-based generalised shared mechanism BCSA cross-user scenario, aims at achieving available with non-fully TPA, and reducing user's fees TPA's pressure by allowing share their procedure others. Furthermore, initialise concrete construction BCSAD Diffie–Hellman protocol for scenario different data. Likewise, also propose novel BCSAI identical data, utilises password-authenticated key exchange (PAKE) achieve ciphertext deduplication, storage alleviating service on server TPA. Security performance analysis evaluate scheme.