信息中心网络使用内容名字驱动的路由和路由器缓存数据来解决IP网络存在的流量激增和移动性问题。但从安全角度，信息中心网络面临诸多威胁，如DDoS攻击、内容污染攻击等。解决这些问题的有效途径之一是确认攻击责任方，并对其采取措施。只有解决了问责问题，才能根本上降低攻击发生概率。信息中心网络的路由、缓存等特点使其他领域问责机制在此不适用。因此，亟须对信息中心网络问责问题展开研究。本项目围绕问责机制设计和问责性模型评价两个科学问题展开研究。项目将综合运用应用密码学、代数编码、图论等基础理论，从数据请求和网络服务两个角度设计可问责安全机制，并使用仿真平台和实验床进行测试验证。项目也充分权衡问责性与隐私的负相关关系，设计两者同时保障的机制；项目还采用基于状态的模型方法对问责机制定量评价，为机制优化提供理论依据。项目成果不仅为解决信息中心网络安全问题提供理论依据和关键技术，还极大促进其他领域问责问题研究。

As a promising next generation network architecture, Information Centric Network (ICN) adopts the techniques of content-name-based routing and caching at the routers to settle the problems of performance and mobility in IP networks. However, ICN still has some security threats, such as DDoS attacks and content pollution attacks. Accountable schemes are needed for ICN to provide security guarantees. Accountable schemes should be provided to find those who are responsible for the attacks, and take measurements to them to defend against the potential attacks. The characteristics of ICN make previous accountable schemes from other scenarios cannot be applied to ICN. Thus, we need to study the accountability issue for ICN. In this proposal, we focus on two scientific problems of mechanism designs and modeling analysis. We endeavor to design the accountable schemes based on applied cryptography, coding theory, and graph theory for both requesting process and serving process in ICN, and use simulators and testbeds to verify the proposed schemes. We also consider the tradeoff between accountability and privacy, and propose the schemes to provide both accountability and privacy guarantees. Moreover, we use the state-based modeling methods to quantitatively analyze the accountability of ICN. All these results are feasible for the realistic scenarios, solid the theoretical foundations of accountability, and provide some experience for other scenarios such as cloud computing and wireless networks.