Broadcasting the encrypted data via cloud storage may greatly ease security concerns.. Security is provided to access data in wireless broadcast services. Symmetric-key-based encryption is used to ensure the authorized users who own the valid keys can decrypt the data. With regard to various subscription activities, an efficient key management for distributing and changing keys is in great demand for the access control in broadcast services. Hence the proposed system namely, key tree reuse (KTR) to handle key distribution with regard to complex subscription options and user activities. It contributes all subscription activities in wireless broadcast services. Instead of separate sets of keys for each program, a user only needs to hold one set of keys for all subscribed programs. KTR identifies the minimum set of keys that must be altered to ensure broadcast security and minimize the rekey cost.

Searchable encryption, data sharing, data privacy

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