Music lovers have reveled in-and devoured-free digital music.The catch is that artists'property rights got lost in the shuffle as online consumers ignored copyright laws that are meant to prevent the unauthorized copying and distribution of recorded music.Without a secure way to track music files online, artists find themselves losing control over their own creations as well as the ability to profit from them.

Enter Digital Media on Demand (DMOD), a Boston-based startup that has made secure distribution of online music its mission.DMOD's four cofounders recognized before most others that digital distribution necessitated technologies to protect and manage artists' rights; they have spent the past several years developing an encryption protocol that will allow artists to encode and track online files. Whereas most encryption systems use one key to provide secure, limited access to a file, DMOD's uses many. In fact, according to Sam Headrick, director of development, a different encryption key could be applied to each second of audio, or for each line of text. "This increases the complexity of cracking the file by many degrees," Headrick says.