Today’s tested NAS unit model has four swappable HDD bays and an internal cache SSD connector as well, full RAID functionality, 2x Gigabit Ethernet (which can be Link Aggregated), USB 3.0 and then a heap of software functionality that is bound to impress. You can hook up the device as just a UPnP server, but extend as much as you want to as this is a download server, FTP server, a MySQL server, a WWW server and well, anything with the word ‘server’ mentioned in it. For your more regular file access the unit is compatible with major OSes, all user and group management based of course. Link