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Rights Management and
Payment Technologies
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may be further limited by media type, geographical distribution, size of production run
or, in the digital environment, number of downloads, and quality.
A typical licence acquisition process will follow these lines:
1.The user attempts to access a protected/encrypted file.
2. A licence is requested, and metadata (usually comprising a unique ID and a set of
attributes) are sent to the licence issuer.
3.The licence server retrieves the appropriate licence from a database using the
metadata.
4. A licence is sent to the user, allowing access to the file.
A number of media viewers handle the licence acquisition process automatically, with
messages being exchanged when a user attempts to view, listen to, or otherwise access
protected content.
Self Protecting Documents and the Digital Object Identifier
Special file or object formats offer an alternative way of protecting content.The Self
Protecting Document (SPD) format was initially developed by Xerox, and is now owned
by ContentGuard Inc.
194
An SPD is a document that preserves its own confidentiality
and integrity, and enforces the rights assigned to it. Documents created in PDF,Word or
HTML format can be converted into SPD, with integrated metadata asserting the creator's
preferences and enforcing conditions of use.
195
Images can be protected in similar ways. Image-server technologies, for example, present
zoomable images that cannot be downloaded or duplicated. Digimarc
196
and MediaSec
197
are companies that provide secure watermarking solutions.There are unsophisticated
ways around this. It remains possible to take a screenshot of the image and paste this into
Adobe
Photoshop or Macromedia Fireworks.
198
The resulting quality, however, will not
be good enough for any purpose beyond primitive Web display. For further protection,
images can be tiled so that would-be pirates need to `stitch' numerous files together to
recreate the full image.
The Digital Object Identifier (DOI) is a system for `identifying and exchanging intellectual
property in the digital environment'.
199
The DOI identifier framework is `media-neutral',
and can be applied to both physical and digital objects whether they are documents, film,
images, or sound files. Given its emphasis on persistence, interoperability and extensibility,
the use of DOIs can be helpful in building automated services and assisted transactions in
e-commerce, particularly in the communications required between different organisations
running different copyright licensing systems.
194 http://www.xerox.com; http://www.contentguard.com
195 There are an increasing number of products in this area. For instance, Homepage Content Guard is a tool
for securing the textual content of Web sites.While it enables viewing, it can be used to make printing and
copying impossible. http://www.softcome.com
196 http://www.digimarc.com
197 http://www.mediasec.com/html/en/index.htm
198 http://www.adobe.com/products/photoshop/main.html; http://www.macromedia.com/software/fireworks/
199 http://www.doi.org/. Issue 4 of the DigiCULT.Info Newsletter carried a brief introduction to DOIs and
pointed to other key sources of information.The September 2003 issue of Ester Dyson's monthly report
Release 1.0 (vol. 21, no. 8) focused on "Online Registries:The DNS and Beyond". In this she put DOIs into
a broader context of persistent handle systems, see http://www.handle.net/.
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