A multikey fully homomorphic encryption privacy protection protocol based on blockchain for edge computing system

Abstract

Summary In order to protect private data in edge computing system and ensure that ciphertexts encrypted under different keys can be processed in the cloud, we propose a privacy protection protocol for edge computing, which is based on blockchain technology and multikey fully homomorphic encryption (MFHE). By constructing a Merkle hash tree and saving the Merkle root node to the blockchain, the integrity of the data in edge nodes is protected. For the data with high computational complexity in edge nodes, the GSW fully homomorphic encryption scheme is employed to process the encrypted private data of a single edge node by the CMS. The LinkAlgo algorithm is applied to link different keys by the relation between them, which enables the CMS to process the encrypted private data of multiple edge nodes. The security analysis and performance evaluation of the proposed privacy protection protocol show that our protocol has high security and good efficiency.