Ext3cow is an open-source, versioning file system based on ext3. It provides a time-shifting interface that allows a real-time and continuous view of the past. This allows users to access their file system as it appeared at any point in time. Click here
for a usage example.
Ext3cow was designed as a platform for regulatory compliance, and has been used to implement secure deletion, authenticated encryption, and incremental authentication. See the publications page
for more details.
Some advantages of ext3cow:
• It does not pollute the name space with named versions
• It has low storage and performance overhead
• It is totally modular, requiring no changes to kernel or VFS interfaces