Cloud with the ability to copy CHANGES in files?

Question

Data synchronization

They puzzled me thoroughly ... In short, you need to solve such a problem at this stage. There is a large container encrypted with truecrypt (60 gigs for example), you need to somehow synchronize it with the cloud. The problem is that it is not possible to upload the modified file every time. A small period of time is allocated for this at the beginning of the working day (say, 5 minutes). Next, the file is mounted in tc and they work with it during the day. Obviously, during this time you can only copy the changes in the file. I checked - when adding / changing files to the tc container, not the entire file changes, but only part of it. Already something. But I have not found a solution to my problem.
PS Tried owncloud - there is no such possibility. You need to find a cloud with such an opportunity or look for workarounds.

Answer 1

Bit torrent sync
Ask your boss for a bonus.
By the way, for complete security, you can not use public trackers for the exchange, this is p2p. Although this is an extra paddock.
And yes, any cloud clients can now download changes. Bit torrent sync just has no limits)