Implementing efficient attribute encryption in IoV under cloud environments

Abstract

CP-ABE is a flexible cryptographic algorithm that enables efficient implementation of access control techniques in cloud architectures. However, when CP-ABE is applied to the IoV environment, the weak performance of IoV individuals will inevitably reduce the efficiency of the overall cryptosystem. In addition, various contingencies in IoV require CP-ABE to be able to dynamically respond to various access requests, and generating only a single ciphertext cannot satisfy various additional access requests. In this paper, we propose an encryption algorithm VM-CP-ABE for IoV in cloud environment, which has the features of offline encryption and outsourced decryption. The offline encryption process utilizes the large amount of offline time of individuals in the vehicular network to generate the initial ciphertext segments, while executing its secret sharing process for each offline phase of the ciphertext segments, thus completing the initial combination of ciphertext parameters. The outsourced decryption can generate transformation keys, thus stripping the most complex pairing operations in the decryption process from the weak performing IoV individuals and transferring this part of operations to the more powerful outsourced individuals. In addition, VM-CP-ABE can generate special hierarchical ciphertexts that will have a smaller ciphertext space. And it can avoid the problem of space efficiency due to the high volume of access control policy transfer. We show the static security of all mechanisms of VM-CP-ABE and conclude with a detailed efficiency analysis. VM-CP-ABE is more time- and space-efficient than traditional attribute encryption for extensive sets of IoV attributes in cloud environments.