Nowadays, network infrastructures are increasingly
used in support to commercialization of digital
multimedia content. Non-material goods (videos,
music, images and any other type of multimedia
information) are migrating from traditional delivery
technologies to a full-electronic delivery model.
Incidentally, the same features that make the
management of digital content so easy are also
responsible for the difficulties of selling it
on-line. Digital information as it is can be easily
copied an unlimited number of times and transferred
to an unlimited number of people. Thus it is of
crucial...