Scalable and Secure Sharing of PHR using Distributed Attribute-Based Encryption in Cloud

Abstract — Cloud computing has emerged as one of the most influential paradigms in the IT industry for last few years. Normally data owners and service providers are not in the same trusted domain in cloud computing. Personal health record (PHR) is an emerging patient-centric model of health information exchange, which is often outsourced to be stored at a third party, such as cloud providers, however the information could be exposed to those third party servers and to unauthorized parties. In the existing system, a novel patient-centric framework and a suite of mechanisms for data access control to PHRs stored in semi-trusted servers. To achieve fine-grained and scalable data access control for PHRs, leverage attribute based encryption (ABE) techniques to encrypt each patient’s PHR file. A high degree of patient privacy is guaranteed simultaneously by exploiting multi-authority ABE. In proposed System, introduce the concept of Distributed Attribute-Based Encryption (DABE), where an arbitrary number of parties can be present to maintain attributes and their corresponding secret keys. Also two-level access control model introduced, that combines fine-grained access control, which supports the precise granularity for access rules, and coarse-grained access control, which allows the storage provider to manage access requests while learning only limited information from its inputs. This is achieved by arranging outsourced resources into units called access blocks and enforcing access control at the cloud only at the granularity of blocks