Identify information sources with different start times in complex networks based on sparse observers

The dissemination of information across various locations is an ubiquitous occurrence,however,prevalent methodologies for multi-source identification frequently overlook the fact that sources may initiate dissemination at distinct initial moments.Although there are many research results of multi-source identification,the challenge of locating sources with varying initiation times using a limited subset of observational nodes remains unresolved.In this study,we provide the backward spread tree theorem and source centrality theorem,and develop a backward spread centrality algorithm to identify all the information sources that trigger the spread at different start times.The proposed algorithm does not require prior knowledge of the number of sources,however,it can estimate both the initial spread moment and the spread duration.The core concept of this algorithm involves inferring suspected sources through source centrality theorem and locating the source from the suspected sources with linear programming.Extensive experiments from synthetic and real network simulation corroborate the superiority of our method in terms of both efficacy and efficiency.Furthermore,we find that our method maintains robustness irrespective of the number of sources and the average degree of network.Compared with classical and state-of-the art source identification methods,our method generally improves the AUROC value by 0.1 to 0.2.

What to Cache：Differentiated Caching Resource Allocation and Management in Information-Centric Networking

Information-centric networking(ICN) aims to improve the efficiency of content delivery and reduce the redundancy of data transmission by caching contents in network nodes. An important issue is to design caching methods with better cache hit rate and achieve allocating on-demand. Therefore, an in-network caching scheduling scheme for ICN was designed, distinguishing different kinds of contents and dynamically allocating the cache size on-demand. First discussing what was appropriated to be cached in nodes, and then a classification about the contents could be cached was proposed. Furthermore, we used AHP to weight different contents classes through analyzing users' behavior. And a distributed control process was built, to achieve differentiated caching resource allocation and management. The designed scheme not only avoids the waste of caching resource, but also further enhances the cache availability. Finally, the simulation results are illustrated to show that our method has the superior performance in the aspects of server hit rate and convergence.

Intelligent Resources Management System Design in Information Centric Networking

Information centric networking(ICN) is a new network architecture that is centred on accessing content. It aims to solve some of the problems associated with IP networks, increasing content distribution capability and improving users' experience. To analyse the requests' patterns and fully utilize the universal cached contents, a novel intelligent resources management system is proposed, which enables effi cient cache resource allocation in real time, based on changing user demand patterns. The system is composed of two parts. The fi rst part is a fi ne-grain traffi c estimation algorithm called Temporal Poisson traffi c prediction(TP2) that aims at analysing the traffi c pattern(or aggregated user requests' demands) for different contents. The second part is a collaborative cache placement algorithm that is based on traffic estimated by TP2. The experimental results show that TP2 has better performance than other comparable traffi c prediction algorithms and the proposed intelligent system can increase the utilization of cache resources and improve the network capacity.

Smart control plane for information centric network-internet service provider networks

The information centric network(ICN)has been widely discussed in current researches.The ICN interoperation with a traditional IP network and caching methods are one of the research topics of interest.For economic reasons,the capability of applying the ICN to internet service providers(ISPs)with various traditional IP protocols already implemented,especially IGP,MPLS,VRF,and TE,does not require any change on the IP network infrastructure.The biggest concern of ISPs is related to their customers’contents delivery speed.In this paper,we consider ICN caching locations in ISP by using the concept of locator/ID separation protocol(LISP)for interoperation between a traditional IP address and name-based ICN.To be more specific,we propose a new procedure to determine caching locations in the ICN by using the cuckoo search algorithm(CSA)for finding the best caching locations of information chunks.Moreover,we create the smart control plane(SCP)scheme which is an intelligent controlling,managing,and mapping system.Its function is similar to the software defined network concept.We show how the proposed SCP system works in both synthetic small network and real-world big network.Finally,we show and evaluate the performance of our algorithm comparison with the simple search method using the shortest path first algorithm.

CMLP: Exploiting Caches at Multiple Levels of Proxies to Enhance Seamless Mobility Support in Information-Centric Networks

The recent evolution of the Internet towards "Information-centric" transfer modes has renewed the interest in exploiting proxies to enhance seamless mobility. In this work, we focus on the case of multiple levels of proxies in ICN architectures, in which content requests from mobile subscribers and the corresponding items are proactively cached to these proxies at different levels. Specifically, we present a multiple-level proactive caching model that selects the appropriate subset of proxies at different levels and supports distributed online decision procedures in terms of the tradeoff between delay and cache cost. We show via extensive simulations the reduction of up to 31.63% in the total cost relative to Full Caching, in which caching in all 1-level neighbor proxies is performed, and up to 84.21% relative to No Caching, in which no caching is used. Moreover, the proposed model outperforms other approaches with a flat cache structure in terms of the total cost.

Neighborhood-Based In-Network Caching for Information-Centric Networks

The current Internet is based on host-centric networking, and a user needs to know the host address before reaching a data target in the network. The new architecture of information-centric networking (ICN) facilitates users to locate data targets by giving their data names without any information about host addresses. In-network caching is one of the prominent features in ICN, which allows network routers to cache data contents. In this paper, we emphasize the management of in-network cache storage, and this includes the mechanisms of cache replacement and cache replication. A new cost function is then proposed to evaluate each cache content and the least valuable content is evicted when cache is full. To increase cache utilization, a cooperative caching policy among neighboring routers is proposed. The proper network locations to cache data contents are also discussed in the paper. Experimental results show the superiority of the proposed caching policy than some traditional caching polices.

ICN Based Vehicle-to-Cloud Delivery for Multimedia Streaming in Urban Vehicular Networks

Mobile multimedia streaming is an open topic in vehicular environment. Due to the high intermittent links, it has become a critical challenge to deliver high quality video streaming in vehicular networks. In this paper, we reform the Information Centric Networking （ICN） concept for multimedia delivery in urban vehicular networks. By leveraging the 1CN perspective, we highlight that vehicular peers can obtain multimedia chunks via the vehicle-to-cloud （V2C） approach to improve the delivery quality. Based on this, we propose a lightweight multipath selection strategy to guide the network system to adaptively adjust the forwarding means. Extensive simulations show that the proposed solution can optimize the utilization of network paths, lighten network loads as well as avoid wasting resources.

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.

基于聚类的ICN缓存空间规划方法

为合理分配信息中心网络(ICN)中每个节点的缓存空间,提出一种基于聚类的ICN缓存空间规划方法。根据节点属性数据集对ICN节点聚类后,以得到的聚类中心属性数据集为每一类分配缓存空间,后根据欧氏距离评估聚类效果为类内每个节点分配缓存空间,来提高缓存系统性能。在实际应用中,也可以为互联网服务提供商(ISP)提供一定的指导意义。仿真结果表明,该方法与均分分配部署方法、基于度数部署方法、基于介数部署方法相比,缓存命中率有明显提高,响应时延明显降低。

基于ICN的数据中心虚拟机动态迁移方法

为了解决传统数据中心网络在支持虚拟机(Virtual Machine,VM)快速动态迁移过程中不能完全避免服务中断的问题,提出了一种基于信息中心网络技术(Information Centric Networking,ICN)的VM动态迁移方法——ICVM。ICVM基于ICN中标识与地址分离的思想,将VM从地址上解耦,路由请求基于VM标识,因此,当VM被迁移到不同的物理机时,其IP、MAC地址可保持不变,服务不会中断。实验结果表明,相较于目前数据中心网络广泛采用的EVPN-VXLAN技术,ICVM不仅支持VM的无缝动态迁移,而且所产生的控制开销数量平均减少了约98%,网络中交换机转发表大小平均减少了约97%,具备很强的扩展性。

ICN网内解析自适应地址选择方法

在信息中心网络中,名字解析系统负责标识与网络地址之间的映射关系的建立、维护和发布。信息中心网络中内容的多副本特性导致标识到地址的“一对多”的映射关系,带来选择适当解析地址的挑战。网内解析作为一种系统驱动的解析模式,将解析能力内生于可编程网络设备中,不可避免地需要进行选址操作。现有的选址方法不能同时提供网络和服务端负载均衡的保障,传统的直接选择、轮询等策略造成解析链路拥塞或服务端负载不均衡。为解决上述问题,本文提出一种自适应的地址选择方法,充分利用软件定义网络的网络感知和处理能力,综合网络状态信息和地址解析频率信息,同时实现服务端与网络链路的负载均衡。仿真结果证明该方法在负载均衡方面的优越性。提出的算法为未来的研究提供新的方向与思路。

基于ICN的数据中心服务调度方法优化设计

虚拟化技术使得数据中心的服务可以在任意位置灵活部署,同时也引入如何合理调度用户的服务请求到这些位置的问题。本文提出一种基于信息中心网络(ICN)技术的数据中心服务调度方法——ICSS。基于ICN标识与地址分离特性,ICSS可直接在网络层数据平面级别提供分布式服务调度功能,网络层数据平面支持线速转发,能实时快速处理服务请求的调度决策,避免传统调度方案在路径延伸和传输时延方面的不足。ICSS考虑服务请求大小及虚拟机资源负载情况,基于PSO-GA算法进行服务调度,以优化服务响应时间和虚拟机负载均衡程度,提高网络的扩展性。为实现与现有数据中心IP业务的无缝承接,本文设计一种ICN协议与IP网络协议的转换方法,确保ICSS对客户端和服务端透明。实验表明,相较于传统的加权最小连接算法(WLC),ICSS的服务完成时间平均减少约21%,CPU、内存资源利用率方差分别平均减少约10%、10%;相较于网络层分布式服务调度方法——分布式计算感知调度算法(CArDS),ICSS在服务请求数量较多时具有更少的服务完成时间,CPU、内存资源利用率方差分别平均减少约32%、29%,转发表表项平均减少约97%,控制开销数量平均减少约98%。ICSS在服务完成时间、负载均衡以及可扩展性方面具有明显优势。

基于F-Stack的高性能ICN网关设计与实现

部署信息中心网络(ICN)协议转换网关是实现ICN与现有IP网络兼容演进的一种方式。为了提升网关在数据流量的处理与转发方面的效率,避免网关的数据处理瓶颈影响ICN提供的性能增益,本文提出一种基于F-Stack开发框架的高性能ICN网关设计方法。该网关系统利用DPDK用户态协议栈快速处理大量TCP连接与流量,并结合DPDK的共享内存与无锁环形队列机制实现进程间通信,不仅具备良好的性能,而且可以降低模块间的耦合性。实验结果表明,在8核CPU资源配置下,本文方法具有良好的性能优势:数据传输速率可达75%网卡线速,同时支持87万个以上的并发连接,且平均处理时延在45μs以下。

面向异构ICN节点的副本选择算法研究

信息中心网络(ICN)是一种革新式网络架构,打破了传统TCP/IP网络端到端传输的限制,提升内容分发效率。ICN构建全网规模的缓存系统,在网络内采用多副本冗余的方式缓存数据内容,以便用户就近获取。与传统互联网缓存系统不同,ICN的缓存呈现泛在化的特点,工作设备是网络基础设施,导致服务资源的异构性普遍存在。在这种环境下,选择适当的副本节点成为重要研究问题。本文首先通过M/M/1排队模型对异构ICN节点进行抽象建模和分析,然后将异构副本节点的选择建模成多臂老虎机问题,继而引入UCB1算法来探索并学习最优决策。仿真实验结果表明,该算法在提高缓存服务可靠性和缩短内容获取时延方面具有明显优势,算法使服务可靠性达到99.15%,将内容获取的平均时延最大缩短8.63%。

ICN中的一种协作缓存机制

为了克服现有Internet架构存在的众所周知的缺点,未来网络的研究成为热点.ICN(information-centricnetworking)在众多新架构中正逐渐被公认为最有前途的方案.它把传输的内容缓存到沿途的节点.高效的缓存机制是它的一个重要研究方面.为此,提出了一种在分布式缓存机制中嵌入中心式缓存决策的机制(content-awareplacement,discovery and replacement,简称APDR),它把内容的放置、发现、替换统一起来考虑,实现内容的有序缓存,提高网络的性能.APDR的主要思想是:Interest报文除了携带对内容的请求以外,还收集沿途各节点对该内容的潜在需求、空闲缓存等信息,使得Interest的汇聚点和目的地节点可以据此计算出一个缓存方案,并把该方案附加在Data报文上,通知返程途中的某些节点缓存该内容并设置指定的缓存时间.在多种实验条件下对APDR进行了仿真验证,结果表明,APDR可以改善网络性能,包括缓存命中率、接入代价、替换数量、转发效率以及缓存鲁棒性等;而且APDR的额外开销也不大.

面向数据新鲜度的ICN-IoT缓存方案

信息中心网络(ICN)缓存能加速物联网(IoT)数据传输并减少数据响应延迟,但现有ICN缓存方案未考虑数据更新频繁与用户的数据新鲜度请求导致缓存效率较低。针对该问题,提出一种基于IoT数据新鲜度的ICN-IoT缓存方案。引入时间戳将用户对数据新鲜度的请求精确到时刻,根据IoT数据的关联性预测未来时刻数据值以满足用户请求,并结合内容流行度与基于时间的请求概率对到达内容做出缓存决策。仿真结果表明,与NDN-PET、NDN-TTL、PCC等缓存方案相比,该方案能有效减少IoT用户获取内容的平均时延并提高信息准确率。

基于节点社团重要度的ICN缓存策略

全网内置缓存是ICN(信息中心网络)架构中最重要的特性之一。为使被缓存的内容对象在空间和时间上分布更合理,提出了一种基于节点社团重要度的缓存策略(CSNIC)。该策略以社团为单位,不仅把内容缓存到社团内用户容易获取的节点处,而且使不同流行度的内容对象在各社团内节点处的时间分布上更合理。在多种实验条件下对CSNIC策略进行了仿真验证,结果表明该策略与CEE-LRU、Betw-LFU、Opportunistic相比,能更好地提升包括缓存命中率、跳数减少率、内容差异性及替换数量等在内的网络缓存性能指标,而且,CSNIC策略的额外开销较小。

物联网中时间驱动的ICN缓存机制研究

在物联网架构设计中采用信息中心网络(information centric networking,ICN)的思想将非常有利于提高信息与数据的传输效率,但现有的ICN缓存机制难以满足物联网用户对信息准确度的要求,尤其是在时间维度上的严格要求。针对这一问题,利用ICN基于内容名命名的方式和内置缓存的特性,提出了一种新的能应用于物联网的时间驱动的普适性缓存方案,创新地在兴趣包和数据包中添加用于精确匹配的时间戳字段。研究了一种时间匹配算法,目的是向消费者返回满足时间容忍阈值的内容,依据内容流行度和时间请求概率,对到达节点的数据包做出缓存决策,通过仿真验证所提方案的有效性。与用户驱动的信息新鲜度机制相比,时间驱动的普适性缓存方案有效地提高了缓存命中率和信息获取的准确率。

ICN体系结构与技术研究

当前的互联网体系结构是基于终端间包交换的点到点连接通信架构。随着实时视频、话音等通信业务量的日益激增,由于TCP/IP体系固有结构的束缚,互联网传输、处理这些实时多媒体数据的能力受到越来越大的挑战,体现在效率低下、用户体验差。信息中心网络应运而生,它将内容与终端位置剥离,通过对内容进行命名和基于内容名字的路由开展了对互联网体系结构变革的研究探索。

基于概率的启发式ICN缓存内容放置方法

提出一种基于概率存储的启发式住处中心网络内容缓存方法(PCP)。主要思想是请求消息和数据消息在传输过程中统计必要信息,当数据消息返回时,沿途各缓存节点按照一定概率决策是否在本地缓存该内容。设计缓存概率时综合考虑内容热度和缓存放置收益,即内容热度越高,放置收益越大的内容被缓存的概率越高。实验结果表明,PCP在缓存服务率、缓存命中率、平均访问延迟率等方面,与现有方法相比具有显著优势,同时PCP开销较小。