The use and dissemination of information and entertainment in digital form has created new issues for authors who wish to maintain ownership over their work. Early digital rights management (DRM) schemes prevented people from illegally copying items like music or movies from digital sources. Among many other serious problems with this approach, the need to copy files for backup purposes, or to use them legally on other devices, doomed this approach. Modern digital rights management technology enables content owners to grant and enforce specific consumer usage rights for digital content.
Asymmetrical cryptography and the use of digital certificates and digital signatures are proposed as part of the technologies to link ownership and access rights to the purchasers of digital media. The use of standards in the development of these methods is essential to ensure portability between devices.










