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.

从不同等级安全与效用分析的新角度，提出了基于模糊层次分析法的DRM安全策略效用评估及其博弈论选取。通过构建安全策略的层次分析结构，采用模糊判断一致矩阵，分析可选安全组件与服务在安全策略中的权重关系，并将所得权重用于计算DRM安全策略组合的实际效用以及进而实现博弈论选取，得出多方安全效用的Nash均衡，即最优均衡安全策略组合及其存在条件。一组典型安全策略的实例分析表明，博弈结果存在2组不同的安全策略组合，内容与服务提供商可根据数字内容购买用户数及平均购买量等应用情形来有效部署DRM系统，从而获得数字版权保护与各方实际收益的均衡。

In multimedia consuming, Digital Rights Management (DRM) is the important means to con¯rm the bene¯ts of both digital contents/services providers and consumers. To keep the DRM system running in order, risk management should be adopted, which identi¯es and assesses the DRM system's security level. Now, the legitimate sharing of copyrighted digital content is still an open issue, which faces severe risks of propertied assets circumvention and copyright infringe-ments. In this paper, we try to highlight a multi-disciplinary method for all-around examinations on risks to digital assets in the contents sharing scenario. The method is a qualitative and quantitative fuzzy risk assessment, which is used for estimating a novel concept called Risk-Controlled Utility (RCU) in DRM. Then, we emphasize on an application case of the emerging trusted computing policy, and analyze the in°uences of di®erent content sharing modes. Finally, we address a business model with some simulation results. The comparison with other methods shows that the fusion of qualitative and quantitative styles can not only evaluate the RCU with uncertain risk events e®ectively, but also provide accurate assessment data for the security policies of DRM.

In recent decade, DRM (Digital Rights Management) has focused on security techniques for solving the issues as the malicious copy, free dissemination and unrestricted abuse of digital contents or assets. Whereas some increasingly enhanced security policies, which were implemented at contents provider-side or user-side, have not brought about optimal utilities for participants in the contents value chain. An analytic hierarchy structure and its algorithm on the assessment on utility factors’ weights for DRM security policies were proposed based on Fuzzy Analytic Hierarchy Process, and then Swarm simulation experiments were further made on the adoptions of typical security policies in combination with the gained weight values. The simulation results show the proposed approach to fuzzy assessments effectively implements rational and optimal decision-making on security policies combinations.