BCAS: A blockchain-based ciphertext-policy attribute-based encryption scheme for cloud data security sharing

Abstract

It is the most important and challenging problem to share the data safely in cloud computing. Some so-called trusted third parties may also infringe users’ data privacy. It is an urgent problem for data owners to share data safely with the designated users rather than the third party or other users. Traditional encryption schemes utilize different keys to produce multiple encrypted copies of the same data for users. It is no longer applicable for cloud data sharing security. Attribute-based encryption can solve above problems, but it needs to rely on trusted third parties to protect the users’ privacy. In this article, in order to address the above problems, we propose a blockchain-based ciphertext-policy attribute-based encryption scheme for cloud data secure sharing without relying on any trusted third parties. Blockchain-based ciphertext-policy attribute-based encryption scheme can protect the rights and security of data owner. Compared with existing cloud security schemes, the proposed scheme has more advantages in terms of the six aspects: (1) data owners have the authority to decide who can decrypt the data; (2) the operations of users are retained permanently, and all records are tamper-proof; (3) our proposed scheme has the characteristic of “one-to-many” encryption, and data is encrypted only once; (4) our scheme does not rely on any trusted third party; (5) in terms of the discrete logarithm problem and decisional q parallel-bilinear Diffie–Hellman exponent problem, we prove that our proposed scheme is secure; and (6) experiment shows that our proposed scheme is more efficient than the comparative scheme.

Blockchain-Based Decentralized Cloud Solutions for Data Transfer

“…Another technique is presented which enables patients to regulate the sharing of their health data by employing an attribute-based encryption scheme in a distributed file system. They illustrate that, together with privacy protection, it also gives the capacity for data secrecy [ 20 ]. The proposed solution can also be compared with Smart Vault, a platform that allows users to exchange files with a predetermined group of individuals.…”

A Review on Challenges in Cloud Computing Security and Recent Researchs

“…Çalışmada [20], bulut ortamında güvenli ve etkin beri paylaşımı kapsamında, mevcut vekil yeniden şifreleme şemalarındaki uygulanabilirlik ve güvenlik ile ilgili yetersizlikleri gidermek için, kimlik tabanlı durumsal vekil yeniden şifreleme şeması (RIB-CPRE-CE) sunulmuştur. Bulut ortamında güvenli veri paylaşımı için blok zincir tabanlı şifreli metin politikalı özellik tabanlı şifreleme şemasının (BCAS) ortaya konulduğu çalışmada [21], veri sahiplerinin veriyi çözebilecek kullanıcıları belirlemesin e imkân sağlayan, kullanıcı işlemlerini süresiz saklayan bireçok şifreleme yaklaşımıyla verinin bir kez şifrelenmesinin yeterli olduğu bir sistem sunulmuştur. Dinamik veri paylaşımının denetimi için sertifikasız çok kopyalı açık bütünlük denetim şemasının (CLMRPIA) sunulduğu çalışmada [22], paylaşılan veriye ait imzanın oluşturulması için kullanıcıların gizli anahtarları kullanılarak veri bütünlüğünün sağlanmaktadır.…”

An efficient and secure data sharing scheme for cloud data using hash based quadraplet wavelet permuted cryptography approach

“…The advantages of this work were high security, increased efficiency, and restricted access control. Zuo et al 31 developed a blockchain based ciphertext policy attribute encryption (BCAS) scheme for protecting the privacy and confidentiality of users' data in cloud. Here, the data security framework was developed without any trusted third party.…”