Cloud-Assisted Mobile-Access of Health Data with Privacy and Audit ability Abstract:- Motivated by the privacy issues, curbing the adoption of electronic healthcare systems and the wild success of cloud service models, we propose to build privacy into mobile healthcare systems with the help of the private cloud. Our system offers salient features including efficient key management, privacy-preserving data storage, and retrieval, especially for retrieval at emergencies, and audit ability for misusing health data. Specifically, we pro-pose to integrate key management from pseudorandom number generator for unlink ability, a secure indexing method for privacy-preserving keyword search which hides both search and access pat-terns based on redundancy, and integrate the concept of attribute-based encryption with threshold signing for providing role-based access control with audit ability to prevent potential misbehavior, in both normal and emergency cases. Anywhere-anytime-accessibl