A Searchable Symmetric Encryption Scheme using BlockChain

TL;DR

This paper proposes a blockchain-based searchable symmetric encryption scheme that enhances data privacy and search efficiency in decentralized cloud storage systems, addressing current limitations of trust and scalability.

Contribution

It introduces a novel model of SSE using blockchain, with security definitions and two schemes tailored for different data sizes, improving privacy and performance.

Findings

Scheme is secure against malicious adversaries

Performance analysis confirms feasibility and efficiency

Supports scalable and private data search in decentralized storage

Abstract

At present, the cloud storage used in searchable symmetric encryption schemes (SSE) is provided in a private way, which cannot be seen as a true cloud. Moreover, the cloud server is thought to be credible, because it always returns the search result to the user, even they are not correct. In order to really resist this malicious adversary and accelerate the usage of the data, it is necessary to store the data on a public chain, which can be seen as a decentralized system. As the increasing amount of the data, the search problem becomes more and more intractable, because there does not exist any effective solution at present. In this paper, we begin by pointing out the importance of storing the data in a public chain. We then innovatively construct a model of SSE using blockchain(SSE-using-BC) and give its security definition to ensure the privacy of the data and improve the search efficiency. According to the size of data, we consider two different cases and propose two corresponding schemes. Lastly, the security and performance analyses show that our scheme is feasible and secure.