KEY AGGREGATE CRYPTOSYSTEM FOR DATA SHARING IN CLOUD STORAGE

Computer Engineering

The important functionality in the cloud storage is data sharing. In this article, we show how to securely, flexibly, and efficiently share data others in cloud storage. Here We describe new technique for public-key cryptosystems which produce constant-size cipher texts such that efficient delegation of decryption rights for any set of cipher texts are possible. The new thing is that one can aggregate any set or kind 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 bendable choices of cipher text set in cloud storage, but the other encrypted files outside the set remain secret. This compact aggregate key can be handily sent to others or be stored in a smart card with very limited secure storage. We give the formal security analysis of our schemes in the standard model. We also describe other application of our schemes. In particular, our schemes give the first public-key patient-controlled encryption for flexible hierarchy, which was yet to be known.

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.