Abstract: The integration of the cloud and mobile computing make users obtain the data and the service more conveniently and efficiently. However, because of the openness of cloud platform and mobile communication network, how to implement the security access and usage of data for mobile cloud computing has to be solved urgently now. An multi-element access control condition based on proxy re-encryption scheme for the security requirement of mobile cloud computing was proposed, which was consisted of system model, algorithm and the description of re-encryption keys. In this scheme, data center in cloud obtained the objective access control condition of users based on their access request, and generated the corresponding re-encryption cipher for the users. The private key of the users could be used to decrypt the cipher. The scheme has achieved the target of multi-element proxy re-encryption without increasing the amount of users' private keys in mobile cloud computing.

Key words: mobile cloud computing; multi-element access control; proxy re-encryption; description of re-encryption key