Prof. Niv Gilboa

The invention is a method for broadcast encryption that allows a broadcaster to send encrypted data to a set of users such that only a subset of authorized users can decrypt said data. The method comprises modifications to the four stages of the basic Cipher-text Policy Attribute- Based Encryption techniques. The method can be adapted to transform any Attribute-Based Encryption scheme that supports only temporary revocation into a scheme that supports the permanent revocation of users.