 It allows up to 50 networked users, and includes a feature called AirTunes (predecessor to AirPlay).The original version (M9470LL/A, model A1084) was introduced by Apple on June 7, 2004, and includes an analog–optical audio mini-jack output, a USB port for remote printing or charging the iPod (iPod Shuffle only), and a single Ethernet port.The USB port cannot be used to connect a hard disk or other storage device.