Ciphertext-Policy Attribute-Based Encryption using quantum multilevel secret sharing scheme

The current society, with a rapidly multiplying data volume, offered new valences and created new opportunities to develop cryptography. Public-key cryptosystems are the most important contribution of modern cryptography. Attribute-based encryption corresponds to the public key cryptography, and enables plain text access only if the user has all the attributes which the original text was encrypted with. There are two types of Attribute-based encryption: Key-Policy Attribute-Based Encryption and Ciphertext-Policy Attribute- Based Encryption. The basic idea of Ciphertext-policy Attribute-based encryption scheme is that a cryptotext is associated to an access policy. In Ciphertext-Policy Attribute-Based Encryption the authorization is included in the encrypted data, and only users who satisfy the associated policy can decrypt the data. Data can be encrypted without knowing the number of users who can decrypt, but only specifying the policy enabling the decrypt. This paper proposes a quantum version of a Ciphertext- Policy Attribute-Based Encryption method. Our version is conceptually close to the classical one, dealing with quantum multilevel secret sharing scheme to encrypt quantum states and with access structures, for decryption.