A method, computer system, and computer program product for restricting
access to digital content data. The disclosed invention stores the
digital content data on a user device, and classifies the digital content
data as either controlled data or non-controlled data. If the digital
content data is controlled data, the disclosed invention stores a trusted
voucher on the user device, the trusted voucher being associated with the
controlled data and comprising at least one permitted function, and
restricts access to the controlled data by the user device to said at
least one permitted function. If the digital content data is
non-controlled data, the disclosed invention associates a local voucher
stored on the user device with the non-controlled data, the local voucher
comprising at least one intended function, and restricts access to the
non-controlled data by the user device to said at least one intended
function.