Cloud Backup

Nowadays, many cloud-based storage solutions provide backups for personal data. While being extremely useful, there are still some problems. For example, how can we make sure that our data is reliably stored? I.e., in case of diasters or the provider goes bankruptcy, our data is not lost. Another concern is that what kind of privacy does cloud storage provides? Are we sure that nobody can view our personal files?

Thus, the goal is of this project is to attack these problems. Specifically, you are expected to implement either one of the following two systems:

• Secure Cloud Backup: your data should be kept encrypted on the cloud side, even the directory or file names should be hidden from the cloud service provider.
• Multi Cloud Backup: your data will be stored on two or more clouds, e.g., 115.com, http://jcube.sjtu.edu.cn/. You are encouraged to support three types of clouds.