Intellectual property management and protection for multimedia content

Nowadays, network infrastructures are increasingly used in support to commercialization of digital multimedia content. Such kind of non-material goods, namely videos, music, still images and any other type of multi-media information are ready for the migration from traditional delivery technologies to a full-electronic delivery model. Incidentally, the same features that make the distribution and 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 importance for a development of the digital multimedia market that exploit the full potential of digital technology to insure that the holders of intellectual property over the content are appropriately rewarded and that only authorized parties can access the valuable information. Moreover, the whole protection system shall be as transparent as possible to the end user in order to assure a maximum of user-friendliness to the process of content consumption. In this scenario interoperability among different manufacturers' products is of critical importance to provide consumers the easiest and most complete accessibility to content. Full interoperability among different devices conceived to consume the same content is provided essentially in two ways. On one side by allowing the same protected content to be consumed on different vendors' devices, and on the other by allowing the same content to be protected by different vendors' protection tools. The first type of interoperability implies that the protection system controlling the use of the content can properly run on different devices and can be implemented and bundled with the content at the time of packaging. This is possible only if the mechanisms involved can be specified in such a way that any compliant device can execute them. Such a standard specification of protection techniques also permits to quantify – in a platform independent way - the computation effort required by the concerned algorithms. Such a piece of information is extremely important when limited resources devices (e.g. mobile terminals) need to state if they are able to properly decode the given content. It is goal of this work to show that a suitable way to standardize the description of protection systems is to provide a behavioural description of terminal reactions to given inputs. In other words, the solution should specify the behaviour, in terms of output data delivered, a given terminal should show when receiving a compliant input stream. The actual implementation of the processing mechanisms allowing the production of the standard output shall not be specified in order to let implementers adopt any kind of preferred (present and future) technology. This Ph.D. work proposes a solution for the implementation of Intellectual Property Management and Protection (IPMP) tools allowing either wide interoperability among different platforms and rapid reconfiguration in case of tampering. The solution implies the definition of a security-oriented meta-language based on a set of ad-hoc primitives executed by a Virtual Machine (Virtual IPMP System). It will be also shown that once an appropriate set of primitive functionality can be defined and used to describe any possible IPMP algorithm, the complexity of the decoding effort for any given input will be able to be specified in a platform independent way.