[Duplicity-talk] the big 'picture' --or-- how to keep just one revision.

[Richard]

I've been trying to comprehend exactly how duplicity will work for me as 
I continue to make backups.  I've been searching the web and the mailing 
list archives  for either a graphical representation or a text version 
of a 'play by play' of what occurs during subsequent backups and cleanups.

In my situation, I am not looking to keep historical revisions of data.  
I only need the current data backed up. 

My understanding is that once an initial backup is made all future 
backups are incrementals.   If after 14 days you need to restore a file 
that changes each day, then the initial backup plus all 13 incremental 
backups will be needed to restore the file.   This would mean that an 
occasional full-backup would be needed if things are to remain 
manageable.   I'm trying to keep from having to continuously backup 
50gig across the net when only 50 meg of data changes each day.

Is it possible to keep just ONE backup on the system and just update 
that one encrypted tar file via rsync?

Is it possible to keep just the original backup and then only one 
differential that grows each day that would contain all of the changed 
data since the original backup?

What happens when a large amount of data disappears from the source 
location?

Here are the google search term's I've used so far in my quest for answers.
+duplicity +"graphic representation" -movie -Theatrical
+duplicity cleanup old backups  -movie -Theatrical -DVD
+duplicity multiple backups -movie -Theatrical -DVD
+duplicity  +"Kenneth Loafman"