Evolution of IPv6 Internet topology with unusual sudden changes

The evolution of Internet topology is not always smooth but sometimes with unusual sudden changes. Consequently, identifying patterns of unusual topology evolution is critical for Internet topology modeling and simulation. We analyze IPv6 Internet topology evolution in IP-level graph to demonstrate how it changes in uncommon ways to restructure the Internet. After evaluating the changes of average degree, average path length, and some other metrics over time, we find that in the case of a large-scale growing the Internet becomes more robust; whereas in a top–bottom connection enhancement the Internet maintains its efficiency with links largely decreased.

Evolution of the Internet AS-level topology:From nodes and edges to components

Studying the topology of infrastructure communication networks(e.g., the Internet) has become a means to understand and develop complex systems. Therefore, investigating the evolution of Internet network topology might elucidate disciplines governing the dynamic process of complex systems. It may also contribute to a more intelligent communication network framework based on its autonomous behavior. In this paper, the Internet Autonomous Systems(ASes) topology from 1998 to 2013 was studied by deconstructing and analysing topological entities on three different scales(i.e., nodes,edges and 3 network components: single-edge component M1, binary component M2 and triangle component M3). The results indicate that: a) 95% of the Internet edges are internal edges(as opposed to external and boundary edges); b) the Internet network consists mainly of internal components, particularly M2 internal components; c) in most cases, a node initially connects with multiple nodes to form an M2 component to take part in the network; d) the Internet network evolves to lower entropy. Furthermore, we find that, as a complex system, the evolution of the Internet exhibits a behavioral series,which is similar to the biological phenomena concerned with the study on metabolism and replication. To the best of our knowledge, this is the first study of the evolution of the Internet network through analysis of dynamic features of its nodes,edges and components, and therefore our study represents an innovative approach to the subject.

Degree and connectivity of the Internet's scale-free topology

This paper theoretically and empirically studies the degree and connectivity of the Internet＇s scale-free topology at an autonomous system （AS） level. The basic features of scale-free networks influence the normalization constant of degree distribution p（k）. It develops a new mathematic model for describing the power-law relationships of Internet topology. From this model we theoretically obtain formulas to calculate the average degree, the ratios of the kmin-degree （minimum degree） nodes and the kmax-degree （maximum degree） nodes, and the fraction of the degrees （or links） in the hands of the richer （top best-connected） nodes. It finds that the average degree is larger for a smaller power-law exponent A and a larger minimum or maximum degree. The ratio of the kmin-degree nodes is larger for larger λ and smaller kmin or kmax. The ratio of the kmax-degree ones is larger for smaller λ and kmax or larger kmin. The richer nodes hold most of the total degrees of Internet AS-level topology. In addition, it is revealed that the increased rate of the average degree or the ratio of the kmin-degree nodes has power-law decay with the increase of kmin. The ratio of the kmax-degree nodes has a power-law decay with the increase of kmax, and the fraction of the degrees in the hands of the richer 27% nodes is about 73% （the 73/27 rule＇）. Finally, empirically calculations are made, based on the empirical data extracted from the Border Gateway Protocol, of the average degree, ratio and fraction using this method and other methods, and find that this method is rigorous and effective for Internet AS-level topology.

Deductive way of reasoning about the internet AS level topology

Our current understanding about the AS level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior （node and edge dynamics） of the individual ASes and generalize the consequences of these individual actions for the complete AS ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole AS system and the consequences of these premises are determined through deductive reasoning. We show that such a deductive approach can give complementary insights into the topological properties of the AS graph. While inductive models can mostly reflect high level statistics （e.g., degree distribution, clustering, diameter）, deductive reasoning can identify omnipresent subgraphs and peering likelihood. We also propose a model, called YEAS, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the AS level Internet.

Performance Evaluation of Topological Infrastructure in Internet-of-Things-Enabled Serious Games

Serious games have recently enticed many researchers due to their wide range of capabilities.A serious game is a mean of gaming for a serious job such as healthcare,education,and entertainment purposes.With the advancement in the Internet of Things,new research directions are paving the way in serious games.However,the internet connectivity of players in Internetof-things-enabled serious games is a matter of concern and has been worth investigating.Different studies on topologies,frameworks,and architecture of communication technologies are conducted to integrate them with serious games on machine and network levels.However,the Internet of things,whose core requirement is the provision of connectivity on the application layer,has different challenges for more dynamic applications such as serious games.The performance of Internet-of-things-enabled serious games depends on the type of infrastructure(wired,wireless)network and Mobile Ad-hoc Network(MANET)and is subtly different from one type of network to another.This paper investigates the connectivity challenges in the Internet-of-thingsenabled serious games using the mentioned infrastructure and identifies the core requirements for these games.It also aims to evaluate various parameters such as reliability,scalability,response time,to name a few,with varying infrastructure and network types.Results highlight the preliminary infrastructure finding and highlight the core setup for which the games are deployed.Moreover,this work will be a steppingstone for architecting the connectivity in serious games in a typical smart space with many infrastructures such as wired networks,wireless networks,and MANET.

Design, Implementation and Verification of Topology Network Architecture of Smart Home Tree

Smart home technology provides consumers with network connectivity,automation or enhanced services for home devices.With the Internet of Things era,a vast data flow makes business platforms have to own the same computing power to match their business services.It achieves computing power through implementing big data algorithms deployed in the cloud data center.However,because of the far long geographical distance between the client and the data center or the massive data capacity gap,potentially high latency and high packet loss will reduce the usability of smart home systems if service providers deploy all services in the cloud data center.Edge computing and fog computing can significantly improve the utilization of network resources and reconstruct the network architecture for the user’s home.This article enables a fog resource-based resource allocation management technology.It provides a method that can more reasonably allocate network resources through a virtualized middle-tier method to ensure low response time and configure Quality of Service to ensure the use of delay-sensitive critical applications to improve the reliability of smart home communication system.Besides,the proposed method has is tested and verified by adjusting the variables of the network environment.We realize the optimization of resource allocation of client network without changing the hardware of client.

Modeling and Mutation Evolution of IPv6 IP-Level Network Topology

In order to understand IPv6 topology characteristics and dynamic behaviors deeply, and guide the design of IPv6 Internet structure, an Internet IP level topology evolution model (IP-TEM) based on power-law distribution was established. Selected the data of IPv6 IP-level topology from CAIDA Internet Global Research Institute in the year from 2012 to 2016 to analyze the evolution characteristics of IPv6 during the probing period, and then introduced to the characteristic outlier weight to locate the mutation time point to analyze the network topology mutation evolution, it is concluded that the evolution trend of other characteristics and the mutation points of each characteristic outlier weight are basically the same except for the average clustering coefficient. Then simulated the normal evolution and mutation evolution of the network respectively using IP-TEM, the simulation results show that IP-TEM can simulate the normal evolution and partial mutation evolution of the real network.

Topology and Position Aware Overlay Network Construction Protocol for Augmentation Information of Satellite Navigation System

It is an effective method to broadcast the augmentation information of satellite navigation system using GEO technology.However,it becomes difficult to receive GEO signal in some special situation,for example in cities or canyons,in which the signal will be sheltered by big buildings or mountains.In order to solve this problem,an Internet-based broadcast network has been proposed to utilize the infrastructure of the Internet to broadcast the augmentation information of satellite navigation system,which is based on application-layer multicast protocols.In this paper,a topology and position aware overlay network construction protocol is proposed to build the network for augmentation information of satellite navigation system.Simulation results show that the new algorithm is able to achieve better performance in terms of delay,depth and degree utilization.

基于微服务和物联网的配电网智能计量架构

为实现电力系统向智能电网模式的演进,依赖于配电网(DN)的自动化,需要新的基础设施、技术和应用。提出一种基于微服务和物联网(IoT)的配电网自动化的智能计量设施,支持各种有助于实现配电网自动化和管理的服务。首先,在测量基础设施中对特定硬件、设备和底层协议进行抽线;然后,利用消息队列遥测传输(MQTT)作为以事件为导向的发布/订阅协议来实现,同时支持发布/订阅和请求/响应机制来实现;最后,使用以大数据为导向的可群集软件模块来实现可扩展性。分布式状态估计(SE)和网络拓扑重构算法验证了智能计量设施支持交互和协同操作。

Internet拓扑建模综述

Internet拓扑建模是在更高层次上开发、利用Internet的基础.Internet拓扑模型研究经历了从随机型到层次型,再到无尺度(scale-free)网络的过程.对包括幂率(power law)在内的多种Internet拓扑特征及其相应度量进行了分析,对现有的拓扑模型、拓扑生成算法以及拓扑生成器进行了全面的综述.最后论述了目前研究中遇到新的问题与挑战,并对今后技术路线进行了总结.

Internet网络拓扑建模

首先概述Internet网络拓扑建模的意义和分类;总结现阶段已发现的主要网络拓扑特性与度量指标;然后分析、讨论自治域级和路由器级的Internet网络拓扑建模与最新的研究成果;最后针对目前拓扑建模中存在的难点和问题给出总结,并展望未来的研究发展方向.

一个Internet路由器级拓扑自动发现系统

本文讨论了一个Internet路由器级拓扑自动发现系统的结构、所遇到的问题和若干关键技术,并实现了一个针对CERNET的拓扑发现原型系统。实验结果表明,发现方法可行,发现原理适合于大规模IP网络,可以拓展为一个发现全国Internet路由器级拓扑的系统。

AS级Internet拓扑层次性分析与建模

基于对AS(autonomous system)级拓扑实测数据的分析,提取出拓扑层次性相关的若干重要特征;给出层次划分的按据、优化参数以及新加入节点的连接细节和非线性择优概率;提出了一种基于核数划分的AS级互联网层次动态演化模型(IAT-HDEM)。对模型进行了计算机建模和数值仿真评估,分析表明该模型能较好地模拟出真实互联网AS级拓扑的宏特征、幂律特性和层次特性。

一种基于AS的Internet拓扑模型

分析Internet中AS的变化规律,提出一种拓扑模型。根据对Internet拓扑变化的统计计算出模型参数。仿真结果表明,该模型生成拓的特性比BA模型更接近Internet。

多点测量Internet路由器级拓扑

随着Internet的快速发展,人们越来越关注对Internet拓扑结构的测量。本文分析了采用公共traceroute服务器进行拓扑测量的局限性,给出了一个等价于在ISP内多点测量Internet路由器级拓扑的三层体系结构,并采用一个统一的三层框架结构来部署和维护相应的系统,特别侧重于系统布置实施和维护的灵活性。通过二阶段随机选择确定探测目标来增强探测过程的弱感知性。采用按需发送每跳所需报文数量、集中进行DNS查询等方法,降低了网络负载,提高了探测性能。通过实践从功能角度评估了测量系统。

基于k-核解析的Internet路由级拓扑的分形特征

通过分析CAIDA Skitter项目授权的海量实测数据,研究了Internet路由级拓扑的分形特征.依据k-核解析的概念将Internet路由级拓扑分成不同的核,通过对各核的度分布、度相关性及聚集性等主要特征量进行分析,发现随着网络由外到内的逐层剪切,不仅度分布,而且聚类性质及相关结构也被保留了下来.这说明Internet路由级拓扑中存在着一种由外向内逐渐趋于网络中心的全局自相似性质,以及根据网络中心性定义的Internet的任意区域都有和整个网络拓扑相同性质的一种结构.Internet路由级拓扑具有分形特征.

一种简单的Internet级联故障模型

介绍了Internet动力学和拓扑特征,分析了引发Internet级联故障的原因,提出了一种简单的Internet级联故障模型(ICFM).仿真实验验证了Internet存在的自组织临界特性,并进一步探讨了该特性可能的成因.该模型将有助于对Internet级联故障的检测和控制技术的研究.

一种基于多项复杂特征的Internet路由级拓扑建模方法

通过对CAIDA多监测点获得的测量数据的分析,提取出表征Internet路由级拓扑规律的多项特征值.在特征值分析的基础上,综合考虑了路由级拓扑的动态变化,拓扑的层次性,以及节点间非线性连接的特点,提出了面向Internet路由级拓扑的DNLH(Dynamic Non-Linear Hierarchy)模型,并给出建模算法.以实际数据为依据,结合遗传算法优化了节点间非线性连接参数.通过实验分析,证明了该建模方法的有效性.

AS级Internet拓扑度和连通性演化分析

Internet拓扑,尤其是AS级拓扑,是目前研究的热点。研究Internet拓扑的演化趋势,可以更好地了解网络的内在连接机制。该项研究基于CAIDA项目授权的海量数据,数据采集时间为2004年1月至2008年6月。首先介绍了必要的基本概念,然后给出了节点平均度、最大节点度值、高度值节点平均度、富人俱乐部连通性和聚集系数的演化分析。研究发现,度值较高的节点,其影响力随时间变化逐渐下降,高度值节点之间的连接也逐渐减少,但网络整体上仍表现出明显的富人俱乐部性质和聚集性。

AS级Internet拓扑突变性分析

通过分析2009年1月至2010年4月间采集的CAIDA自治域级数据,研究发现:网络规模、节点间连接程度和聚集性随时间有增加的趋势.依据k-核解析的概念将网络分成不同的层,具体针对网络特征值有跳跃性变化的时间点,分析该时间点各层度分布、层节点数、层连接分布和层节点度总和的变化.结果表明:此时间点低层节点数明显减少但连接概率增加,影响网络连接程度的主要因素是中间层间节点的连接变化,突变性变化使网络处于不稳定状态,网络有自我调节能力,会逐渐恢复稳定状态.利用信息熵概念引入适用于Internet的标准结构熵概念,进一步验证了拓扑中小涨落的影响积累到一定程度时,系统就会产生"巨涨落",表现为特征值突变.