Due to the difficulty and capacity, cryptography to a cloud is to be one of the most effective attributes for big data storage and access. However, verifying the access legitimacy of a user and securely updating cryptography in the cloud based on a new access policy selected by the data owner...

Last year, the European Commission proposed a comprehensive reform of the EU’s data protection rules. The proposed regulation has been surrounded by fierce controversy and has been the subject of frenzied lobbying by global corporations, industry groups, research centres and privacy...