Well rsync has some flags you can give so when the connection between hosts is re-established the rsync starts without any problems.
In order to transfer "file-i-want-to-transfer.txt" from local server to a remote server I hit the following command and even if the connection is dropped at some point, once the connection is reestablished the rsync will resume where it was left over:
rsync --progress --archive --compress --partial --append --recursive file-i-want-to-transfer.txt [email protected]:/tmp/file-i-want-to-transfer.txt
What does the above parameter do you ask? Well ... the following:--progress = show the progress bar
And that's it...