【作者】 徐明明；

【导师】 王海艳；

【作者基本信息】 南京邮电大学 ， 计算机软件与理论， 2012， 硕士

【摘要】 随着互联网技术的不断发展,网络安全问题日益突出,近年来如何有效地构建可信网络已成为业界研究和关注的热点之一。然而几乎所有的攻击事件都是从终端发起的,因此研究基于终端的网络连接控制尤为重要。可信网络连接(Trust Network Connect,TNC)理论是在保障终端硬件安全的基础上,将原有的信任链扩展到网络,从而整体提高网络的可信性和可靠性。本课题所研究的终端可信接入和远程证明技术亦是可信网络连接相关理论的研究重点。终端可信接入技术的深入研究可以保证终端主机的个体安全,而远程证明机制研究则是使将终端可信延伸至网络环境中,保证整个网络环境的可信,两者的相互融合进一步保证网络的整体可信。论文充分研究课题的相关背景知识,分析和改进现有的研究所存在的不足,引用和借鉴有效的专业理论知识,为构建一种可实现的可信网络提供有效的理论支持。文中所作的具体工作主要包括以下三个方面:首先,在可信网络连接体系结构下,结合终端完整性度量,对终端引入“稳定度”概念,即通过对终端接入结果和其历史接入记录的实时分析计算出终端的“稳定度”,进而提出一种可行的基于接入终端稳定度的可信网络修复方案。与已有的基于完整性验证的修复技术相比,该方案能及时发现和选择性修复不满足可信网络安全策略的终端修复属性,为终端用户提供及时可靠的修复服务。实验结果表明:利用该方案能有效保证终端安全性与稳定性,同时能有效快速修复失败接入终端。其次,针对现有可信计算组织定义的远程证明机制证明过程复杂和隐私泄漏的不足,通过使用基于双线性映射的BBS+签名算法和属性证书机制代替平台配置信息的方式,提出了一种基于双线性映射和属性证书的远程证明方案(bilinear mapping and property-based attestation,BMPBA)。与已有的远程证明方案相比,BMPBA方案更好地降低了平台配置信息易泄露的风险,其使用的签名方案具有密钥与签名长度短和计算效率高的优点,从而提高了远程证明机制的运行效率。分析结果表明:利用该方案能够高效率地实现平台间的远程证明,并能较好地保证平台证明的安全性、正确性和不可伪造性。最后,设计并实现了TNC测试环境。与此同时,测试环节详细制定有效的网络安全策略,并进行相应的功能性测试,之后的仿真实验证明了引入终端稳定度概念的实质意义。更多还原

【Abstract】 With the continuous development of Internet technology, network security has became more and more important, how to build a trusted network effectively is the most concerned issue in recent years. Since almost all of the attacks are started from the terminal, the research on network connection control based on terminal is particularly important. Trust Network Connect is to extend trust chain to the network on the premise that terminal’s hardware security is well protected, so the entire network can be credible and reliable. Trusted terminal access and remote attestation are key issues in the field of Trust Network Connect. The former technology could ensure the individual safety of terminal while the latter could extend trust and the combination of them would ensure the credibility of the entire network. In this paper, we study the drawbacks of existing mechanisms and propose an effective theory to build a trusted network, main work can be concluded into the following three parts:Firstly, to improve the effectiveness of control and remediation of failure access terminals in trusted network, a novel remediation scheme is proposed in this paper. Based on the introduction of a definition of stability of access terminals and the employment of the architecture of trusted network connect (TNC), the proposed remediation scheme can not only realize a dynamic control on terminal’s behaviors but also support a trustworthy remediation. Simulation results demonstrate that the proposed scheme is more effective compared with static and integrity-based remediation scheme and significantly improve the speed of remediation.Secondly, since TCG-defined remote attestation is not sufficient for complicated attestation and privacy leaks, a bilinear mapping and property-based attestation scheme named BMPBA was proposed through using BBS+ signature based on bilinear mapping and property-based certificate instead of platform configuration information. Compared with the current remote attestation scheme, the risk of leaking platform configuration information could be better reduced; meanwhile the efficiency of remote attestation could be improved because of the shorter key and higher computing speed. The analysis shows that remote attestation between platforms could be efficiently implemented by using BMPBA, and the security, validity and enforceability of platform attestation also could be guaranteed.Finally, a TNC test environment is designed and implemented in this paper, meanwhile we formulate an effective network security strategy and have some correspondent functional test. The simulation result on terminal stability index shows that the introduction of terminal stability has a profound significance.更多还原