Tip from http://www.linuxquestions.org/questions/linux-networking-3/scp-resume-aborted-download-290836
If the following command aborted,
$ scp file_to_transfer user@remotehost:/path/remote_file
then use rsync to resume:
$ rsync --partial file_to_transfer user@remotehost:/path/remote_file
And
$ export RSYNC_RSH=ssh
to use ssh as the transport layer.
