A system and a method for providing variable security mechanisms for
securing digital content, in which a single security mechanism is not
used for all content. Instead, at least one characteristic or feature of
the security mechanism is varied between units, instances or categories
of content. Therefore, even if unauthorized access is gained to a single
unit of content, the overall integrity and security of the system for
content distribution is not compromised. Preferably, security is provided
through a general mechanism, which is then varied in order to provide
variable, dissimilar security schemes for different types of content. By
"type of content", it is meant any of a single unit of content, a single
instance of content or a single category of content. For example, for a
category of content, the content may be characterized according to the
identity of the content itself, such as the title of a movie for example,
and/or according to the owner of a particular copy of the content. Thus,
different security schemes may optionally and preferably be generated
from a particular root structure. Related apparatus and methods are also
provided.