Privacy Protection Method of Document Management Based on Homomorphic Encryption on the Fabric Platform

Certificates of assets and capabilities contain personal privacy information. At present, certificate management still adopts the traditional centralized management method, and the registered information is stored in a clear text, thereby leading to a weak tamper resistance of information and is not conducive to the protection of privacy information. Ciphertext storage leads to the difficulty of information query and statistics. In addressing the two problems mentioned above, this study applies blockchain and homomorphic encryption technology in certificate management system, and proposes to use Paillier homomorphic encryption algorithm under Fabric blockchain platform to protect personal privacy, realize ciphertext storage of personal information, improve the ability to resist external network intrusion, and use the homomorphic additivity of Paillier algorithm to create statistics on data in ciphertext space thus improving the protection of users' privacy information. Finally, in accordance with the method proposed in this study, the chaincode is written, and the blockchain network performance under the chaincode is tested using the caliper test framework. The BatchTimeout and PreferredMaxBytes parameters are optimized to reduce the delay in time and improve the throughput rate of the system.