An Efficient Update Strategy for Content Synchronization in Content-Centric Networking(CCN)

Content-centric Networking(CCN) is progressively flattering the substitutable approach to the Internet architecture through illuminating information(content) dissemination on the Internet with content forenames.The emergent proportion of Internet circulation has expectant adjusting Content-centric architecture to enhance serve the user prerequisites of accessing content.In recent years,one of the key aspects of CCN is ubiquitous in-network caching,which has been widely received great attention in research interest.One foremost shortcoming of in-network caching is that content producers have no awareness about where their content is put in storage.Because routers in CCN have caching capabilities,therefore,each and every content router can cache the content item in its storage capacity.This is problematic in the case in which a producer wishes to update or make the changes in its content item.In this paper,we present an approach regarding how to address this issue with a scheme called efficient content update(ECU).Our proposed ECU scheme achieves content update via trifling packets that resemble contemporary CCN communication messages with the use of additional table.We measure the performance of ECU scheme by means of simulations and make available a comprehensive exploration of its results.

A Survey of Applications Research on Content-Centric Networking

As a named data-based clean-slate future Internet architecture,Content-Centric Networking(CCN)uses entirely different protocols and communication patterns from the host-to-host IP network.In CCN,communication is wholly driven by the data consumer.Consumers must send Interest packets with the content name and not by the host’s network address.Its nature of in-network caching,Interest packets aggregation and hop-byhop communication poses unique challenges to provision of Internet applications,where traditional IP network no long works well.This paper presents a comprehensive survey of state-of-the-art application research activities related to CCN architecture.Our main aims in this survey are(a)to identify the advantages and drawbacks of CCN architectures for application provisioning;(b)to discuss the challenges and opportunities regarding service provisioning in CCN architectures;and(c)to further encourage deeper thinking about design principles for future Internet architectures from the perspective of upper-layer applications.

Exploring Hits-Based Content Provisioning Mechanism in Content-Centric Networking

In-network caching and Interest packets aggregation are two important features of Content-Centric Networking(CCN).CCN routers can directly respond to the Interest request by Content Store(CS)and aggregate the same Interest packets by Pending Interest Table(PIT).In this way,most popular content requests will not reach the origin content server.Thus,content providers will be unaware of the actual usages of their contents in network.This new network paradigm presents content providers with unprecedented challenge.It will bring a great impact on existing mature business model of content providers,such as advertising revenue model based on hits amount.To leverage the advantages of CCN and the realistic business needs of content providers,we explore the hits-based content provisioning mechanism in CCN.The proposed approaches can avoid the unprecedented impact on content providers' existing business model and promote content providers to embrace the real deployment of CCN network.

Degree-Based Probabilistic Caching in Content-Centric Networking

Content-Centric Networking is a novel future network architecture that attracts increasing research interests in recent years. In-network caching has been regarded as a prominent feature of Content-Centric Networking since it is able to reduce the network traffic, alleviate the server bottleneck and decrease the user access latency. However, the CCN default caching scheme results in a high caching redundancy, causing an urgent need for an efficient caching scheme. To address this issue, we propose a novel implicit cooperative caching scheme to efficiently reduce the caching redundancy and improve the cache resources utilization. The simulation results show that our design achieves a higher hit ratio and a shorter cache hit distance in comparison with the other typical caching schemes.

Super Node Routing Strategy in Content-Centric Networking

There were two strategies for the data forwarding in the content-centric networking(CCN): forwarding strategy and routing strategy. Forwarding strategy only considered a separated node rather than the whole network performance, and Interest flooding led to the network overhead and redundancy as well. As for routing strategy in CCN, each node was required to run the protocol. It was a waste of routing cost and unfit for large-scale deployment.This paper presents the super node routing strategy in CCN. Some super nodes selected from the peer nodes in CCN were used to receive the routing information from their slave nodes and compute the face-to-path to establish forwarding information base(FIB). Then FIB was sent to slave nodes to control and manage the slave nodes. The theoretical analysis showed that the super node routing strategy possessed robustness and scalability, achieved load balancing,reduced the redundancy and improved the network performance. In three topologies, three experiments were carried out to test the super node routing strategy. Network performance results showed that the proposed strategy had a shorter delay, lower CPU utilization and less redundancy compared with CCN.

Comprehensive Analysis of Caching Performance under Probabilistic Traffic Patterns for Content Centric Networking

The phenomenon of data explosion represents a severe challenge for the upcoming big data era.However,the current Internet architecture is insufficient for dealing with a huge amount of traffic owing to an increase in redundant content transmission and the end-point-based communication model.Information-centric networking(ICN)is a paradigm for the future Internet that can be utilized to resolve the data explosion problem.In this paper,we focus on content-centric networking(CCN),one of the key candidate ICN architectures.CCN has been studied in various network environments with the aim of relieving network and server burden,especially in name-based forwarding and in-network caching functionalities.This paper studies the effect of several caching strategies in the CCN domain from the perspective of network and server overhead.Thus,we comprehensively analyze the in-network caching performance of CCN under several popular cache replication methods(i.e.,cache placement).We evaluate the performance with respect to wellknown Internet traffic patterns that follow certain probabilistic distributions,such as the Zipf/Mandelbrot–Zipf distributions,and flashcrowds.For the experiments,we developed an OPNET-based CCN simulator with a realistic Internet-like topology.

Content Centric Networking: A New Approach to Big Data Distribution

In this paper, we explore network architecture anal key technologies for content-centric networking （CCN）, an emerging networking technology in the big-data era. We descrihe the structure anti operation mechanism of tl CCN node. Then we discuss mobility management, routing strategy, and caching policy in CCN. For better network performance, we propose a probability cache replacement policy that is based on cotent popularity. We also propose and evaluate a probability cache with evicted copy-up decision policy.

A Survey on Information-Centric Networking: Rationales, Designs and Debates

The basic function of the Internet is to delivery data(what) to serve the needs of all applications. IP names the attachment points(where) to facilitate ubiquitous interconnectivity as the current way to deliver data. The fundamental mismatch between data delivery and naming attachment points leads to a lot of challenges, e.g., mapping from data name to IP address, handling dynamics of underlying topology, scaling up the data distribution, and securing communication, etc. Informationcentric networking(ICN) is proposed to shift the focus of communication paradigm from where to what, by making the named data the first-class citizen in the network, The basic consensus of ICN is to name the data independent from its container(space dimension) and session(time dimension), which breaks the limitation of point-to-point IP semantic. It scales up data distribution by utilizing available resources, and facilitates communication to fit diverse connectivity and heterogeneous networks. However, there are only a few consensuses on the detailed design of ICN, and quite a few different ICN architectures are proposed. This paper reveals the rationales of ICN from the perspective of the Internet evolution, surveys different design choices, and discusses on two debatable topics in ICN, i.e.,self-certifying versus hierarchical names, and edge versus pervasive caching. We hope this survey helps clarify some mis-understandings on ICN and achieve more consensuses.

Caching Algorithm with a Novel Cost Model to Deliver Content and Its Interest over Content Centric Networks

Recently the content centric networks(CCNs) have been advocated as a new solution to design future networks. In the CCNs, content and its interest are delivered over the content store and pending interest table, respectively, where both have limited capacities. Therefore, how to design the corresponding algorithms to efficiently deliver content and inertest over them becomes an important issue. In this paper, based on the analysis of content distribution, status of content store, and pending interest, we propose a novel caching algorithm with which the resources of content store and pending interest table can be efficiently used. Simulation results prove that the proposal can outperform the conventional methods.

Exploring Content Popularity in Information-Centric Networks

Information-Centric Networking(ICN), an alternative architecture to the current Internet infrastructure, focuses on the distribution and retrieval of content by employing caches in a network to reduce network traffic. The employment of caches may be accomplished using graph-based and content-based criteria such as the position of a node in a network and content popularity. The contribution of this paper lies on the characterization of content popularity for on-path in-network caching. To this end, four dynamic approaches for identifying content popularity are evaluated via simulations. Content popularity may be determined per chunk or per object, calculated by the number of requests for a content against the sum of requests or the maximum number of requests. Based on the results, chunk-based approaches provide 23% more accurate content popularity calculations than object-based approaches. In addition, approaches that are based on the comparison of a content against the maximum number of requests have been shown to be more accurate than the alternatives.

Proposed Caching Scheme for Optimizing Trade-off between Freshness and Energy Consumption in Name Data Networking Based IoT

Over the last few years, the Internet of Things (IoT) has become an omnipresent term. The IoT expands the existing common concepts, anytime and anyplace to the connectivity for anything. The proliferation in IoT offers opportunities but may also bear risks. A hitherto neglected aspect is the possible increase in power consumption as smart devices in IoT applications are expected to be reachable by other devices at all times. This implies that the device is consuming electrical energy even when it is not in use for its primary function. Many researchers’ communities have started addressing storage ability like cache memory of smart devices using the concept called—Named Data Networking (NDN) to achieve better energy efficient communication model. In NDN, memory or buffer overflow is the common challenge especially when internal memory of node exceeds its limit and data with highest degree of freshness may not be accommodated and entire scenarios behaves like a traditional network. In such case, Data Caching is not performed by intermediate nodes to guarantee highest degree of freshness. On the periodical updates sent from data producers, it is exceedingly demanded that data consumers must get up to date information at cost of lease energy. Consequently, there is challenge in maintaining tradeoff between freshness energy consumption during Publisher-Subscriber interaction. In our work, we proposed the architecture to overcome cache strategy issue by Smart Caching Algorithm for improvement in memory management and data freshness. The smart caching strategy updates the data at precise interval by keeping garbage data into consideration. It is also observed from experiment that data redundancy can be easily obtained by ignoring/dropping data packets for the information which is not of interest by other participating nodes in network, ultimately leading to optimizing tradeoff between freshness and energy required.

CCN中选择性缓存机制的研究

现有Internet架构存在着众所周知的缺点,未来网络架构的研究成为了热点.其中,CCN(Content-Centric Networking)在众多新架构中正逐渐被大家认为是最有前途的方案之一,它要求网络中的每一节点都要有缓存功能.所以,研究高效的缓存机制就成为实现CCN预期目标的关键.针对CCN现有缓存机制中存在的"无序缓存"的问题,文中提出了选择性缓存机制SC(Selective Caching).它根据用户的潜在需求和内容的流行规律,只在必要的节点上选择性地(而不是沿着内容传输路径处处地)缓存.同时,采用带宽换缓存的思想,利用链路的冗余带宽,将内容分流到相邻节点缓存,进一步提升缓存效率.我们首先提出了缓存空间消耗的理论分析模型,然后在多种实验条件下对SC进行了验证,实验结果表明SC可以提高网络的缓存效率和性能,同时SC的通信、计算、状态记忆等额外开销也都很小.

CCN中基于节点状态模型的缓存污染攻击检测算法

针对内容中心网络中的缓存污染攻击问题,以污染内容数量、分布状态和攻击强度3个参数对缓存污染攻击进行定量描述和分析,建立了攻击下的节点缓存状态模型。通过分析节点关键参数的变化,提出了基于节点状态模型的攻击检测原则,并分别以单位时间缓存替换率和请求达到率为观测参数进行算法实例化设计。仿真结果与性能分析表明,所提检测算法在应对分散式攻击与集中式攻击时,可以取得良好的检测性能。

CCN中基于业务类型的多样化内容分发机制

针对内容中心网络(Content Centric Networking,CCN)如何提供差异化的业务需求服务的问题,采用区分服务的思想,从内容传输和缓存决策的角度出发,提出了一种基于业务类型的多样化内容分发机制.该机制依据不同的业务请求特征,分别设计了持久推送、并行预测和逐包请求的数据分发模式,对应提出了透明转发、边缘概率缓存和渐进式推进的沿途存储策略,实现了内容传递对于业务类型的感知和匹配.仿真结果表明,该机制减小了内容请求时延,提高了缓存命中率,以少量额外的控制开销提升了CCN网络整体的内容分发性能.

CCN中基于替换率的缓存空间动态借调机制

针对内容中心网络(CCN,content centric networking)节点存储资源的有效利用和优化配给问题,在同质化缓存分配的基础上,提出了一种基于替换率的缓存空间动态借调机制。该机制从节点存储空间使用状态的动态差异性出发,首先对于缓存资源借调的合理性给予证明,进而,依据节点对于存储资源的需求程度,动态地执行缓存借调,将相对空闲的存储资源分配给需求程度更大的节点支配,换取过载节点缓存性能的提升。该机制减小了内容请求跳数,提高了缓存命中率,以少量额外的代价换取了内容请求开销的显著下降,提升了存储资源整体利用率,仿真结果验证了其有效性。

基于内容流行度的移动CCN缓存策略研究

近年来,为了适应互联网应用由发送者驱动的端到端通信模式向接收者驱动的海量内容获取模式的转变,并从网络体系架构层面提供对可扩展和高效内容获取的原生支持,研究界近年来提出以内容为中心的新型网络(content-centric networking,CCN)体系架构,它能够高效地支持未来互联网上的内容分发。随着移动用户数量的不断增加,未来移动用户也将访问CCN网络,针对内容中心网络中的用户移动性问题,提出了一种基于内容流行度的移动性缓存策略。该策略考虑用户移动性,利用半马尔科夫模型对用户移动性进行建模,同时采用多元线性回归模型对内容流行度进行预测,结合用户移动性与原有内容流行度提出一种移动性缓存策略。仿真实验表明,移动性的加入会对内容的流行度产生较大的影响,该策略能有效地提升缓存命中率。

CCN中一种基于流行度的邻居协作缓存策略

为了提高内容中心网络(CCN)的缓存利用率,提出了一种基于流行度的邻居协作缓存策略(PNCC).通过邻域节点间相互协作,根据本节点的数据内容的流行度及来自邻居节点的相同数据内容的请求数,计算出数据传输代价差.根据代价差,PNCC把返回数据存储到流行度最大的节点或其邻居协作缓存节点,以降低数据的传输代价和提高邻域缓存空间的利用率.对缓存已满节点选择流行度最小的数据替换;通过邻居标识表记录邻居节点上存储的内容,让请求内容更准确地获取到邻域存储资源.仿真结果表明,本策略能有效地提高缓存命中率,降低了用户获取数据的时间以及减少了数据传输的跳数.

基于层次划分的CCN网络缓存存储策略

针对如何提高内容中心网络网内缓存性能的问题,提出一种基于层次划分的轻量协作的缓存存储策略。该策略通过Interest分组、Data分组以及路由器本地PIT表三者的协作把内容划分为多种优先级层级,使不同内容缓存在沿途的不同路由器。实验证明该策略可以有效地减少访问跳数,提高平均缓存命中率,降低服务器负载。

一种软件定义的内容中心网络SD-CCN结构

为了应对网络数据的指数式增长以及满足未来网络对内容的需求,结合内容中心网络(sontent centric network,CCN)和软件定义网络(software defined network,SDN)2种未来互联网结构的优势,提出一种软件定义的内容中心网络结构(software defined content centric network,SD-CCN)。SD-CCN以SDN中分离控制平面与数据平面为核心原则,以CCN中基于内容的分发作为主要目标,其基本组成包括控制平面、控制通道、数据平面和数据通道4个部分。所有的控制决策都由控制平面发出,所有的数据操作都在数据平面完成。仿真实验结果表明,该结构相比传统的内容中心网络具有更小的网络开销。

一种基于SDN的CCN集中控制缓存决策方法

在软件定义网络(SDN)和内容中心网络(CCN)融合架构下,为了充分利用控制层对网络拓扑和缓存资源的全局感知,在全网中实现缓存资源的优化使用,提出了一种集中控制的缓存决策优化方案。在该方案中,应用粒子群优化算法(PSO)并且根据节点边缘度、节点重要度以及内容流行度对缓存资源和内容进行集中缓存决策,使得内容在不同的节点进行合理的缓存。仿真结果表明,通过评估缓存大小对缓存性能的影响,PSO缓存决策方法取得了比LCE、PROB缓存决策策略更优的缓存命中率和路径延展率,明显降低了缓存节点的缓存替换数,使得缓存达到了整体缓存优化。