How can I connect to DESY, Zeuthen from outside or from home?
There's a variety of methods, documented here: http://dv-zeuthen.desy.de/services/remote_login/
How can I transfer data from/to Storage at DESY, Zeuthen?
The best method is generally to use our GRID Storage Elements.
If this is not possible, use the dedicated system transfer.ifh.de and scp. This system is accessible from outside - it has to be because many labs and universities obviously do not offer such a service.
Do not use the public login linux systems, or you may find your account in the list of those with usage restrictions on them.