Cooperative and Non-Cooperative Game-Theoretic Analyses of Adoptions of Security Policies for DRM

Digital Rights Management ecosystem is composed of various participants, which adopt different security policies to meet their own security requirements, with a goal to achieve individual optimal benefits. However, from the perspective of the whole DRM-enabling contents industry, a simple adoption of several increasingly enhanced security policies does not necessarily implement an optimal benefit balance among participants. A game-theoretic analysis of adoptions of security policies was emphasized based on a proposed General DRM value chain ecosystem without the loss of generality. First, we formalized security policies and fundamental properties that include internal relativity and external one, together with multiparty game on adoptions of security policies. Also, a cooperative game among digital Contents Provider, Rights/Service Provider and digital Devices Provider, as well as a non-cooperative game between Providers and Consumers were presented. Final, a stable core allocation of benefits and Nash Equilibriums were found out, respectively. It is clearly concluded that the cooperative game has important super-addivitity and convexity, thus simultaneous adoptions of security policies with external relativity being helpful to achieve Pareto Optimality by using a pre-established cooperative relation; and that Pareto Optimality also exists between Providers and Consumer with the increase of users´ purchase transactions when both have a repeated game.