A one-way hash function is applied to a seed supplied by an application to produce a hashed seed that is used to generate the application storage key. A one-way hash function is applied to a seed supplied by a user to produce a first hashed seed that is passed to a keyed hash function, which is keyed to an identity for the user, to produce a second hashed seed. The second hashed seed is used to generate the user storage key. An operating system storage key is generated from an unhashed seed. One of the storage keys is used to encrypt the downloaded content. An access predicate attached to the content when it is downloaded is associated with the storage key to enforce certain limitations on the access of the content.

 
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