Anonymous attribute-based broadcast encryption with hidden multiple access structures

Abstract

Due to the high demands of data communication, the broadcasting system streams the data daily. This service not only sends out the message to the correct participant but also respects the security of the identity user. In addition, when delivered, all the information must be protected for the party who employs the broadcasting service. Currently, Attribute-Based Broadcast Encryption (ABBE) is useful to apply for the broadcasting service. (ABBE) is a combination of Attribute-Based Encryption (ABE) and Broadcast Encryption (BE), which allows a broadcaster (or encrypter) to broadcast an encrypted message, including a predefined user set and specified access policy to install the authorization mechanism. It is desirable to hide all the information when producing in the ciphertext, which has not been considered in the previous works of ABBE. Motivated by the above issue, we devise a solution to achieve anonymity for the ABBE scheme, which not only hides the access structures but also anonymizes the user’s identity. In this work, we propose two schemes as Anonymous Key Policy (AKP)-ABBE and Anonymous Ciphertext Policy (ACP)-ABBE with supporting multiple access structures by using \(\textsf {OR}/\textsf {AND}\) gates. Specifically, we present the generic constructions of AKP/ACP-ABBE on the building block of the Inner Product Encryption (\(\textsf {IPE}\)), which enables the hidden user’s identity and complex \(\textsf {OR}/\textsf {AND}\)-Gate access structure. We show that our proposed schemes are secured under the standard models.