RFD Use git for off-site backups

Hello,
I am thinking about using git for doing differential backups of a whole
machines. And I would like to know what is necessary to obtain that. In
such a scenario the machine to be backed up should have a local index
file but sends its objects directly to the remote machine via git-via-ssh
or git protocol. Is it possible to store extra information like extended
attributes / acls in git? I don't care about named pipes, sockets and
device files for the moment.

        Thomas