Dynamic Location Information in Attribute-Based Encryption Schemes

Attribute-based encryption (ABE) allows users to encrypt (cloud) data with fine-grained Boolean access control policies. To be able to decrypt the ciphertext, users need to have a private key with the associated attributes. If the attributes satisfy the formula, the plaintext can be recovered. In this paper, ABE is extended with dynamic attributes. This allows attributes to be added to an existing private key. A server component named Attribute Authority is introduced. By using these dynamic attributes, it is now possible to have the decryption depend on data that changes often, such as location information of a mobile device. Two schemes were developed that convert location data into usable ABE attributes. To demonstrate our results, an Android application was implemented and evaluated in a field test.