YI Cloud: Improving user privacy with secret key recovery in cloud storage

Cloud Storage systems provide user a safe and consistent place to save user´s valuable data and documents. However, user´s files are not encrypted on some open source cloud storage systems, such as Hadoop and Sector. The storage service provider can easily access the user´s files. This brings a big concern about user´s privacy. This paper describes a cloud storage system named YI Cloud. This system allows the users to encrypt their files in the cloud storage. User´s primary encryption key is shared between trusted entities using secret sharing algorithm. The primary key can be recovered when the user loses it. User´s privacy is protected because user´s files are encrypted in cloud storage. Using secret sharing algorithm, the YI Cloud also decreases the risk that user may lose all his/her encrypted files if he/she loses the encryption key.