Efficient and Secure Ciphertext-Policy Attribute-Based Encryption Without Pairing for Cloud-Assisted Smart Grid

Abstract

Cloud-assisted smart grid has been broadly deployed to improve the economics, efficiency, sustainability, and reliability of electricity services. The new revolution of technology will also bring new challenges to data security, particularly data confidentiality. As a promising encryption method for supporting fine-grained access control, attribute-based encryption (ABE) is widely given attention by the academia and industry. However, most existing schemes suffer from the efficiency problem limiting its deployment for the cloud-assisted smart grid, especially for resource-limited users. To address this problem, this paper proposes two efficient pairing-free ciphertext-policy attribute-based schemes that eliminate the computation-intensive bilinear pairing operation. The basic scheme only uses some simple scalar multiplications based on elliptic curves, and the enhanced scheme provides an important usability feature, namely the users and attributes revocation. The security of the proposed schemes is reduced to the elliptic curve decisional Diffie-Hellman problem. Finally, the performance analysis and extensive experiments demonstrate that our proposed schemes are suitable for the cloud-assisted smart grid. INDEX TERMS Cloud-assisted smart grid, access control, ciphertext-policy attribute-based encryption, pairing-free.

Efficient Revocable Multi-Authority Attribute-Based Encryption for Cloud Storage

“…When a user's attribute is revoked, other user with this attribute will be affected. Wang et al [26] presented efficient and secure CP-ABE without pairing, which can achieve attribute revocation. Although [25] [26] are pairing-free based on ABE, they only support single authority, not multi-authority.…”

“…The scheme [25] supports LSSS access structure, pairing-free and attribute revocation, but it can't realize multi-authority. The scheme [26] supports Tree access structure, pairing-free and attribute revocation, but it can't realize multi-authority. In the above schemes, only the proposed scheme uses LSSS access structure to realize MA-ABE without pairing operation, and supports attribute revocation.…”

“…Suppose there are k attribute authorities, and the attributes number for the DC obtaining from each attribute authority are same, the number is set as j. Since the schemes [25][26] are single-authority, the simulation result of computation costs and storage overhead are one-order equation, the schemes [11,[13][14][15][16][17][18][19][20][21][22][23] and the proposed scheme are multi-authority, the simulation result of computation costs and storage overhead are binary one-order equation, the performance analysis should be discussed separately.…”

“…Compared with the schemes [11,[13][14][15][16][17][18][19][20][21][22][23], the proposed scheme saves 95%, 96%, 97%, 93%, 97%, 92%, 97%, 92%, 95%, 93%, 95%, 97% of the computing cost respectively. Because the schemes [25][26] are single authority, for k = 10, the encryption computation cost of the schemes [25][26] respectively is equal to 11.9381 ms and 12.3232 ms. The decryption computation cost of the schemes [25][26] respectively is equal to 23.106 ms and 19.6401 ms.…”

“…When the key is distributed by central authority, we can consider it as centralized multi-authority ABE scheme [10]. When the key is distributed by attribute authority, we can consider it as decentralized multi-authority ABE scheme [2][3][4][5][6][7][8][9][11][12][13][14][15][16][17][18][19][20][21][22][23][25][26].…”