[Duplicity-talk] The workings of duplicity

[Haim Dimer]

Hi there,

I have a question about the workings of duplicity.

As I understand it, the data is sent by chunks through the facility 
that librsync provides, only sending the chunks that have changed from 
one backup to the next. To do so, I imagine that librsync compares the 
2 files, the original and the most recent backup, so as to determine 
what part of that file changed.

Now since the file is stored encrypted, librsync does not have access 
to the decrypted backup. Or does it? How does the comparison happen 
since the remote backup is encrypted? Where does the decryption happen?

Thank you for your answers.

Haim.