中文摘要：

目前P2P环境下的数字版权管理DRM（Digital Rights Management）方案对于权力转让的支持不太完善,并且对转让过程有一定限制。对于这个问题,首先讨论了目前P2P环境下权力转让可能面临的一些安全威胁,然后结合现有的权力转让方案的种种问题总结了权力转让过程中必须具备的三点性质。最后提出了一个基于电子货币（E-Cash）的权力转让方案,并对其算法、流程作了详细的描述,并且进一步分析了其安全性。该方案比传统的方案更加灵活、安全,能够有效地防止权力的滥用。

英文摘要：

Digital rights management（DRM） in current P2P environment does not perfectly support rights transfer,and has certain restrains on transfer process. For this issue,in the paper first we discuss the security menace the rights transfer may encounter in existing P2P networks,then we summarize three indispensable properties in the context of rights transfer according to a variety of problems in current rights transfer schemes. At last,we propose an e-cash based rights transfer scheme in P2P networks and expound its algorithm and flow,its security is further analysed as well. In comparison with traditional ones,e-cash based mechanism is more flexible and secure,the abuse of the rights is prevented effectually.