APPLSS: Adaptive Privacy Preserved Location Sharing Scheme Based on Attribute-Based Encryption

Unauthorized access to location information in location-based service is one of the most critical security threats to mobile Internet. In order to solve the problem of quality of location sharing while keeping privacy preserved, adaptive privacy preserved location sharing scheme called APPLSS is proposed, which is based on a new hierarchical ciphertext-policy attribute-based encryption algorithm. In the algorithm, attribute authority sets the attribute vector according to the attribute tags of registration from the location service providers. Then the attribute vector can be adaptively transformed into an access structure to control the encryption and decryption. The APPLSS offers a natural hierarchical mechanism in protecting location information when partially sharing it in mobile networks. It allows service providers access to end user's sensitive location more flexibly, and satisfies a sufficient-but-no-more strategy. For end-users, the quality of service is obtained while no extra location privacy is leaked. To improve service response performance, outsourced decryption is deployed to avoid the bottlenecks of the service providers and location information providers. The performance analysis and experiments show that APPLSS is an efficient and practical location sharing scheme.