Certificateless public auditing protocol with constant verification time

To provide the integrity of outsourced data in the cloud storage services,many public auditing schemes which allow a user to check the integrity of the outsourced data have been proposed. Since most of the schemes are constructed on Public Key Infrastructure (PKI), they suffer from several concerns like management of certificates. To resolve the problems, certificateless public auditing schemes also have been studied in recent years. In this paper, we propose a certificateless public auditing scheme which has the constant-time verification algorithm. Therefore, our scheme is more efficient than previous certificateless public auditing schemes. To prove the security of our certificateless public auditing scheme, we first define three formal securitymodels and prove the security of our scheme under the three security models.