A PHR service allows a patient to create, manage, and control her Personal health data storage, retrieval and sharing of the medical information in web. The patient could actually control the sharing of their sensitive Personal health information‟s are stored on a third party server which people may not fully trusted. To ensure patient centric privacy control over their own PHR have fine-grained access control mechanisms that work in the semi trusted servers and the PHR owner encrypt her file should only be available decrypt it. Each attribute authority (AA) in it governs disjoint subset of user role attributes, while none of them alone is able to control the security of the whole system. We propose mechanisms for key distribution and encryption so that PHR owners can specify personalized fine-grained role based access policies during file encryption. In the personal domain, owners directly assign access privileges for personal users and encrypt PHR file under its data attributes MA-ABE by putting forward an efficient on demand user/attribute revocation scheme, and prove its security under standard security assumptions
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PHR, Attribute Based Encryption (ABE), Multi Authority Attribute Based Encryption (MAABE).