The International Journal of Innovative Research in Computer and Communication Engineering
In a cipher text policy attribute based encryption system, a user's private key is associated with a set of attributes and an encrypted cipher text will specify an access policy over attributes. A user will be able to decrypt if and only if the user attributes satisfy the cipher text's policy. With the recent adoption and diffusion of the data sharing paradigm in distributed systems such as online social networks or cloud computing, there have been increasing demands and concerns for distributed data security. One of the most challenging issues in data sharing systems is the enforcement of access policies and the support of policies updates.