Scalable and Secure Data Sharing in Cloud Storage using Aggregate Key Generation Algorithm

In Cloud Computing data storage and data sharing is an important and efficient technique. In this paper we will show how efficiently, securely and Flexibly method to share data with other people in cloud storage system. This system produce constant-size cipher texts such that efficient delegation of decryption rights for any set of cipher texts are possible. The novelty is that one can aggregate any set of secret keys and make them as compact as a single key, but encompassing the power of all the keys being aggregated. In other words, the secret key holder can release a constant-size aggregate key for flexible choices of ciphertext set in cloud storage, but the other encrypted files outside the set remain confidential. In other words, the secret key holder can release constant-size aggregate key for flexible choices of ciphertext set in cloud storage, but the other encrypted files outside the set remain confidential. This compact aggregate key can be conveniently sent to others or be stored in a smart card with very limited secure storage. We provide formal security analysis of our schemes in the standard model. We also describe other application of our schemes.