Glass Mastering comprises a number of stages needed to create a metalized glass master from which the stampers are produced for the DVDs to be stamped/replicated
Encryption CSS/Marcovision is done at the replication facility when making the Glass-master, depending on the replication facility you may be able to send your DVD-r master to the replicator and have them add the CSS/Marco-vision when creating the glass-master
Duplication is done with a CD/VD duplicator which you can purchase for a couple grand, you buy blank media and burn the Disc your self or have someone else do it for you
Replication is the process of making a glass-master, Stamper and the DVDs are manufactured and not burnt to blank media.
maybe that helps
Regards,
Michael Autery
DVD-Makers.com
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