A system is described for linking traditional media works, such as print
and broadcast media for example, to a more interactive media conduit,
such as the Internet. The system avoids the need to modify the media work
in anyway. Instead, it employs a passive recognition system that uniquely
identifies the specific work, such as a particular television or radio
broadcast or printed commercial. The identification may be based in
intra-work and/or extra-work information. Several different
embodiments/environments are described. The best embodiment may depend,
at least in part, on costs of hardware and communication. These costs can
change over time. In one embodiment, all of the databases and computation
are performed at the user's premises. In another embodiment, all of the
databases and computation occur at remote sites that user premise
equipment can query using uniquely identifying extra-work information,
such as the time, place and station on which the work was broadcast. This
second embodiment is most suitable for content that is published, e.g.
magazines, newspapers, etc., or broadcasted, e.g. cable, satellite and
terrestrial television and radio. Alternative embodiments, in which
various operations are performed at both the user's premises and remote
locations are also possible.