本书系统地介绍了内容中心网络的发展及其路由方法。全书包括内容中心网络核心技术、内容中心网络路由机制、内容中心网络缓存机制，以及内容中心网络安全研究。第1章为绪论；第2章介绍了内容中心网络的命名技术、路由与转发技术及缓存技术；第3章介绍了内容中心网络的相关路由方法；第4章介绍了内容中心网络的缓存决策及缓存替换策略；第5章讨论了内容中心网络在安全路由方面的研究。

前言 传统的基于TCP/IP协议的网络体系结构逐渐呈现出许多问题，如网络容量难以支持千倍流量的增长、网络能耗及比特成本开销较大等，无法适应当前移动互联网的发展。在TCP/IP协议中，主机通过IP地址进行身份标识，数据包在传输过程中封装源IP地址与目的IP地址，并根据路由表进行转发，最终找到目标主机。这种“主机-主机”的传输机制可以很好地运行在客户机/服务器模式下的应用场景，但是随着移动互联网、物联网、云计算、雾计算等应用的兴起，用户请求的内容已从简单的网页文字转变为多媒体业务，用户更加关心如何快速获取所需的内容，而并不关心该资源存放的具体位置。为了从根本上解决传统的“以主机为中心”的TCP/IP通信模式造成的问题，科研人员设计了新一代以内容为中心的网络体系结构，即内容中心网络（Content-Centric Networking，CCN），以适应未来海量、新型网络应用的需求。 CCN网络将传统TCP/IP模型中的IP承载层更换为内容承载层，使用内容名字替代IP 地址，进行定位、路由及传输，为用户提供端到内容服务。同时，CCN 网络也扩展了路由节点的功能，将只具有转发功能的传统节点扩展成同时具有存储与转发功能的CCN 节点，提升了网络的传输能力。但是，CCN 网络仍存在一些关键问题，其中之一就是如何设计高效、可靠的路由方法。当前的CCN 路由方法只考虑了兴趣包如何找到发布者服务器上存储的内容，却没有考虑实时的网络状态和网络中普遍存在的大量相同缓存对路由的影响，造成CCN 路由机制的平均请求内容的时延增大，CCN 的分布式缓存资源被浪费。因此，探讨在新型内容中心网络体系结构下的路由方法具有重要意义。本书以内容中心网络为基础，对数据路由的技术知识及面临的挑战进行阐述。 本书以作者自身科研项目为基础，系统地介绍了内容中心网络的发展及其路由方法。全书内容共分5 章，其中，第1 章为绪论，主要介绍内容中心网络体系结构、内容中心网络研究现状及发展趋势；第2 章介绍内容中心网络的命名技术、路由与转发技术及缓存技术；第3 章介绍内容中心网络的相关路由方法；第4 章介绍内容中心网络的缓存决策及缓存替换策略；第5 章讨论内容中心网络在安全路由方面的研究。 本书的显著特色主要包括：①目前虽有研究内容中心网络路由机制的相关文献，但缺乏考虑在高速移动环境下由于网络节点不能快速自适应路由的选择，所导致的网络通信时延增加、链路失效等问题，而本书将内容中心网络中节点对数据的处理与编码技术有机结合，提出了基于网络编码的路由方法，解决了在实时多变情景下路由的选择问题。②针对内容中心网络中突发流量导致的通信负载加大的问题，提出了基于势能的缓存决策策略，并通过考虑节点的情景度，提出了基于情景度的缓存决策策略；在缓存替换方面，分别提出了基于势能冷却的缓存替换策略及基于通告转移的缓存替换策略。③对内容中心网络安全研究进行了深入的调研与分析，系统阐述内容中心网络中的安全问题，提出一系列安全路由方法及隐私保护策略。本书包含国内外许多专家的重要思想成果，但主要内容是作者近几年来的研究成果（部分研究成果公开发表在国内外重要刊物上，得到了国内外同行专家的认可）。其研究内容能够为研究CCN 体系结构的学者们提供一定的借鉴与启发，同时为研究生从事相关研究提供较好的参考。本书既可作为计算机、网络、通信等方向的研究生教材或相关专业本科生的选修课教材，也可作为相关IT 从业人员的技术参考材料。本书主要由张建伟完成，在撰写过程中参考了课题组前期研究成果及相关硕士生论文。特别感谢为此书撰写做出贡献的郑州轻工业大学朱亮讲师、蔡增玉副教授、张焕龙副教授、孙海燕副教授，以及研究生王文倩、栗京晓、杜春峰、吴作栋等。 本书的研究得到国家自然科学基金面上项目（61672471、61873246）、国家自然科学基金青年项目（61902361）、河南省科技创新人才计划杰出人才项目（184200510010），以及郑州轻工业大学的资助，在此表示感谢！ 鉴于作者的知识水平有限，加之撰写时间仓促，书中难免有错误与不足之处，恳请读者批评指正。 张建伟 郑州轻工业大学 2019 年10 月

第1章 绪论··············································································.1 1.1 内容中心网络概述···························································.2 1.1.1 网络体系结构的基本概念及分类································.2 1.1.2 网络体系结构的演进···············································.4 1.1.3 内容中心网络的工作机制·········································25 1.1.4 研究挑战······························································26 1.2 内容中心网络研究现状·····················································28 1.2.1 缓存策略研究························································29 1.2.2 路由转发策略研究··················································32 1.2.3 内容命名机制研究··················································33 1.2.4 网络安全机制研究·················································.34 1.3 内容中心网络发展趋势···················································.35 1.3.1 服务规模与可扩展性··············································.36 1.3.2 支持主动防御的网络安全技术··································.37 1.3.3 基于内容寻址的服务承载网·····································.38 1.4 小结···········································································.38 参考文献············································································.39 第2章 内容中心网络核心技术····················································.43 2.1 内容中心网络内容命名技术·············································.44 2.1.1 扁平化命名机制····················································.45 2.1.2 层次化命名机制····················································.45 2.1.3 两种命名机制的比较··············································.46 2.2 内容中心网络内容名字查找技术·······································.47 2.2.1 名字查找技术·······················································.47 2.2.2 主要性能指标·······················································.48 2.3 内容中心网络路由与转发技术··········································.49 2.3.1 CCN路由基本原理················································.49 2.3.2 CCN转发基本原理················································.55 2.3.3 CCN路由转发面临的问题·······································.58 2.4 内容中心网络缓存技术···················································.59 2.4.1 典型缓存替换策略··················································59 2.4.2 典型缓存决策策略··················································62 2.4.3 CCN缓存策略的四大特征········································67 2.5 小结·············································································69 参考文献··············································································70 第3章 内容中心网络路由机制研究···············································75 3.1 研究背景·······································································76 3.1.1 与传统TCP/IP网络的路由区别··································76 3.1.2 CCN路由协议现存问题···········································78 3.2 内容中心网络路由概述·····················································80 3.2.1 内部路由协议························································80 3.2.2 外部路由协议························································82 3.2.3 分布式路由机制·····················································82 3.2.4 集中式路由机制·····················································84 3.2.5 CCN路由选择策略·················································86 3.3 基于网络编码的自适应路由方法·········································87 3.3.1 基于位置变化的自适应路由模型································93 3.3.2 实验环境配置························································97 3.3.3 实验结果分析·····················································.100 3.4 小结··········································································.102 参考文献···········································································.103 第4章 内容中心网络缓存机制研究·············································.107 4.1 研究背景····································································.108 4.1.1 内容缓存技术的演进·············································.108 4.1.2 内容缓存技术的特征·············································.111 4.1.3 内容缓存技术面临的问题·······································.114 4.2 内容中心网络缓存决策··················································.120 4.2.1 缓存决策概述······················································.121 4.2.2 基于势能的缓存决策策略（PECDS） ·······················.127 4.2.3 基于节点情景度的缓存决策策略（CSNC）················.138 4.3 内容中心网络缓存替换策略············································.149 4.3.1 缓存替换策略概述················································.149 4.3.2 基于势能冷却的缓存替换策略（PEC-Rep） ···············.152 4.3.3 基于通告转移的缓存替换策略·································.159 4.4 小结··········································································.170 参考文献···········································································.171 第5章 内容中心网络安全机制研究···········································.175 5.1 内容中心网络面临的安全威胁·········································.176 5.1.1 内容非授权访问···················································.176 5.1.2 用户隐私泄露······················································.178 5.1.3 兴趣包泛洪攻击··················································.182 5.2 内容中心网络安全保护机制············································.186 5.2.1 隐私保护···························································.186 5.2.2 路由与转发安全··················································.190 5.2.3 缓存安全···························································.198 5.3 内容中心网络中的隐私保护············································.202 5.3.1 内容中心网络缓存的隐私保护策略··························.202 5.3.2 内容中心网络命名的隐私保护策略··························.212 5.3.3 内容中心网络路由与转发的隐私保护策略·················.217 5.4 内容中心网络安全路由方法············································.222 5.4.1 内容中心网络节点路由安全问题分析·······················.222 5.4.2 内容中心网络节点路由安全保护方案·······················.225 5.5 未来展望····································································.232 5.6 小结··········································································.233 参考文献···········································································.234