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Services to create and administrate user accounts and authorize reading devices and applications.
Overview of Users Books - Bokskya Bookshelf
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It is the publisher who decides which DRM to use on the e-book. It is also an option not to use any DRM (NoDRM). DDS support to three types of DRM:
Adobe Content Server 4 (TDRM) - being phaced out
Watermarking (SDRM)
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