The current version of DataGuard comes with three translational layer.
DB2
Gmail
Amazon S3
We are still working to improve the system and add new functionalities.
We are close to releasing the code for other translational layers. Those are:
Flickr - Privacy preserving storing and sharing of images.
Google Calendar - Privacy preserving calendar.
Google DocsSpreadsheets - Privacy preserving documents sharing.
Open problems
In DataGuard, we only considered the problem of accessing data remotely. When it
comes to personal information another requirement is the ability to share it.
DataGuard middleware could be extended to allow data sharing as well. This raises
many interesting challenges, since to enable data sharing the untrusted server should
authenticate users and distribute data. This needs to be done in a fashion where the
server does not learn any user's data.