International Journal of Innovative Research in Science, Engineering and Technology (IJIRSET)
Cloud storage is storage of online data in cloud that is accessible from multiple resources. Cloud storage can provide good accessibility and reliability, towards the data stored in cloud. In cloud storage data sharing is one of the important functionality. In key aggregate cryptosystem, the novelty is that one can aggregate a set of secret keys and make it as a single key, but that single key possesses the power of all the keys being aggregated. All the files stored in the cloud need to be in an encrypted format for that advanced encryption standard is used for encryption and decryption.