In Greek mythology, Phaethusa ("radiance") was a daughter of Helios and Neaera, the personification of the brilliant, blinding rays of the sun. With her sister, Lampetia, she guarded the cattle of Thrinacia[?].
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An early example of a DRM system is the Content Scrambling System (CSS) employed by the DVD Consortium[?] on movie DVD disks. The data on the DVD is encrypted ...