The archival corollary to "Quis custodiet ipsos custodes?" would be "Who digitally copies the digital copies?" As we digitally images our manuscripts, we must ask how will we be maintain the digital images as they become more prolific than the originals? DVD images may become corrupt as soon as 20 years or may last considerably longer. The US Library of Congress has risen to task of copying their materials with robots. In the Time Magazine video below, the inventor of the system discusses his system which copies video media en masse.