Attribute-based Encryption (ABE)
It is a type of encryption protocol that implements role-based access control, which allows the user and providers of the data to encrypt and decrypt based on their personal attributes. This can be a number of things such as department, location, gender, role, age, etc.[3] This would allow the device, in this case, mobile systems to adhere to data access policies outline by the data owner via a ciphertext. It can only be deciphered using a secret key by the other users with the correct attribute information. This process has four steps; first, the system sets up the algorithm and parameter. After this process, a public key (PK) and a system master secret key (MK) will be produced. The second process will then take the PK and encrypt the message. Next, a secret key(SK) is then generated to associate the user attributes. Lastly, the message can be decrypted via all the secret keys (SK). While a very robust method for data security, it still has some flaws to be worked out. The Ciphertext generation and computation have a high cost to them; the calculation has a major impact on the mobile system's performance due to the CPU chip's limited abilities. The sending of the Ciphertext can also be very costly over networks, and certain bandwidth resources could be used up. The secrete key generation can also be costly due to the size of the Ciphertext. All in all, there exists scalability problems within this mobile data security methodology.