How is all the music on the network stored?

I can't seem to find referance to any of this, in the white papaer or on the net in general.
I came across the OPUS project during my search and it clearly states how to intend to store the artists tracks on a decentrilised storage network, called Interplanetary File System (IPFS)

I'm curious on how this is solved, seems like a very import fact, esspecially if the data upload by the artists remains their data and not stored on a centrilized server that could have data removed.