E-Amusement
IIDX RED was the first version of IIDX to require the network for unlocking songs. Unfortunately, this move is seen as an issue for importers of IIDX machines as e-Amusement is not available outside of Japan. e-Amusement can also pull score for a player on a song onto the score graph over the network. Users with e-Amusement cards will also now receive notifications if they beat their personal best score. Using a special e-Amusement card shipped with the home version of Beatmania IIDX 8th Style unlocks 3 extra songs.
Read more about this topic: Beatmania IIDX 11 IIDXRED