OBDD-based network reliability calculation

An efficient method for evaluating the terminal-pair reliability based on an edge expansion tree and using an OBDD (ordered binary decision diagram) is presented. The effectiveness of the algorithm is demonstrated on the larger benchmarks collected in previous work. One notable case of the experimental results for a 2×20 lattice network is that the number of nodes in the OBDD is linearly proportional to the number of stages. This is significantly superior to previous algorithms which are based on the sum of disjoint products and has exponential complexity     

节点不完全可靠无向网络k-端可靠度计算

可靠性是保障网络系统正常运行的必要条件,k-端可靠性问题是网络可靠性的最一般问题.通过对已有的计算2-端可靠度的方法进行扩展和改进,提出了一种计算节点不可靠无向网络k-端可靠度的方法.先将图的边定义为链路及其端点,然后通过矩阵变换运算,得到不相交的k-端路径,在此基础上,利用条件概率对k-端路径的概率进行求解以得到网络...     

通信网可靠性综合评估

影响通信网的可靠性因素很多。在考虑多个测度指标的情况下,通信网可靠性评估是多指标的综合评价,提出了三种综合评估方法。其中基于神经网络的综合评判较好地解决了综合评价指标中各指标的权数确定又尽可能地排除了人为因素的影响这一难题。     

Fuzzy logic based network reliability evaluation

A method for evaluation of the reliability of a network and its nodes is suggested reflecting the customers' requirements and needs stated in linguistic form. The method uses the fuzzy logic to formulate criteria for reliability evaluation and grading on a percentage scale. An illustrative example is included.     

Sequential evaluation of terminal pair reliability in a reliability network

For a non-series-parallel reliability network, the terminal pair reliability is evaluated sequentially and the model is extended to consider the possibility of improving the reliability of a link by a parallel duplication.     

A recursive method for network reliability measures evaluation

A new recursive method for evaluation of reliability measure of the communication networks is given in this paper. The main idea of this method is based on the generation of aggregated networks related to the partitions on subsets of node set. Having found the probabilities of the networks states composing the aggregated network, reliability measures can be obtained by summing up the suitable probabilities of the aggregated networks.     

On the evaluation of telecommunications network reliability usingrouting models

A reliability measure that takes into account routing and rerouting policies after failures as well as the capacity of the network to satisfy its demand is proposed. The measure, based on the evaluation of the lost call traffic, needs resolution of a routing model for the states of perfect functioning as well as the most probable failure states. A type of routing model useful for network planning is also proposed. The model is closer to reality and easier to implement than the other classical multicommodity formulations. A convex-simplex implementation with a reoptimization feature explicitly adapted to the proposed model is used     

基于交换机配置行为的网络可信性评估

在广泛应用的局域网中,网络数据的转发主要靠网络交换机设备来实现,网络管理员需要对网络交换机进行配置才可以实现网络具体的功能,网络数据转发的有效性受网络交换机配置的影响。文章对网络的不可信任问题进行了分析,提出了网络交换机配置行为的网络可信性评估方法;针对网络交换机配置和功能,提出了基于交换机配置行为的网络可信性评估框架,以保证网络设备的运行可以满足用户对网络的可信性要求。     

The recursive variance-reduction simulation algorithm for network reliability evaluation

This paper proposes a new formulation of the recursive variance-reduction Monte Carlo estimator of the /spl kappa/ terminal unreliability parameter of communication systems. This formulation allows significant reduction in the simulation execution time, as demonstrated by experimental results.     

光纤通信网可靠性评估方法及其应用研究

首先,构建了光纤通信网可靠性评估指标体系,在此基础上设计了光纤通信网可靠性评估模型,主要包括链形系统和栅格形系统.然后,搭建实验系统,分析组网方式、典型干线和重要节点对网络可靠性的影响,验证了光纤通信网可靠性评估模型,提出了提高网络可靠性的相关建议措施,为光纤通信网的可靠性评估提供了新思路和新方法.     

基于贝叶斯网络的装备供应链可靠性评估模型

为对装备供应链可靠性进行评估,构建了一种基于贝叶斯网络的评估模型.首先,阐述了装备供应链可靠性的基本概念,然后,介绍了装备供应链的主要环节,最后,根据贝叶斯网络的基本原理,将装备供应链的故障树模型转化为贝叶斯网络模型.     

A new hierarchical belief-rule-based method for reliability evaluation of wireless sensor network

With the wide applications of wireless sensor network (WSN), its reliability evaluation has been attracted more attention. The reliability of a WSN is affected mainly by internal and external factors, which include internal faults and external attacks. In this paper, a reliability evaluation method based on a hierarchical belief rule base (BRB) method is proposed for the reliability evaluation of the WSN. First, the factors affecting the reliability of a WSN are analysed, and the reliability evaluation process that considers the WSN fault evaluation and WSN security evaluation is described. Second, the reliability evaluation model is constructed based on the hierarchical BRB model. The qualitative knowledge is used by the BRB model to build initial belief rules, and the quantitative data are used to optimize the initial parameters of the BRB model, which can utilize various types of uncertainty information effectively. Therefore, the proposed method can be applied to the WSN reliability evaluation, which is a complex and uncertain problem. Finally, a simulation case study and an actual case study of wellhead blowout monitoring are conducted to verify the effectiveness of the proposed method. The reliability results of actual WSN are obtained by the standard testing method, where the loss and accuracy rates of the collected data are treated as the observation factors for obtaining the actual reliability values. The estimated results of hierarchical BRB model are very close to the actual reliability values, which shows that the proposed method can be used for evaluating the reliability of the actual WSN accurately.     

基于多因子分析的无线传感器网络可靠性评估模型设计

采用判决反馈方法评估无线传感器网络时,仅从网络链路稳定性因素方面考虑,未考虑影响网络可靠性的多种因素,自适应能力和可靠性评估效果差。设计基于多因子分析的无线传感器网络可靠性评估模型,利用多因子分析过程将无线传感器网络复杂的变量关系简单化。由5个主指标与20个有相互关联的子指标建立无线传感器网络可靠性评估指标体系,通过主成分分析方法分析指标体系获取11个无线传感器网络可靠性指标主因子。将这些因子输入神经网络模型中,构建无线传感器神经网络可靠性评估模型,完成无线传感器网络可靠性评估。实验结果表明,该模型的可靠性评估精度均值为98%,该模型下的无线传感网络可靠性最高达到98%,极大提高了无线传感器的安全性能。     

轨道交通无线网络通信中的可靠性评估系统改进设计

传统轨道交通通信网络可靠性评估系统无法均衡自身的硬件承载性能,常常丢失轨道交通运行中产生的数据,评估准确度较低。因此,对轨道交通无线网络通信中的可靠性评估系统进行改进设计。该系统由传感器模块、ZigBee技术模块、网关模块和计算机组成,传感器模块用于收集轨道交通通信网络系统运行节点数据,并交由ZigBee技术模块进行数据处理。ZigBee技术模块通过其中的路由器采集数据,通过ZigBee网络协调器解析路由器中的数据,构建持续工作体系,并将体系中的数据传输到网关模块。网关模块依据电平的变化将ZigBee技术模块处理过的数据转变为易于计算机解析的串口数据,将此数据交由通用分组无线业务进行协议更新后,传输到计算机中进行可靠性评估分析。评估软件中设计了对轨道交通无线网络通信可靠性进行评估的流程图和关键代码。结果表明,所设计的可靠性评估系统拥有较高的评估准确度。     

Hypermedia and network reliability

A simple algorithm utilizing the factoring theorem and other elementary network reductions is available to determine network reliability in a number of different forms. This paper describes a computer-based implementation of such an algorithm housed in a hypermedia environment. The environment can provide for both the formulation and the solution of reliability problems. In our treatment the user draws the network interactively on the computer screen and clicks an on-screen button to perform the reliability analysis. This provides an alternative to manual calculations that become tedious or impossible with networks which are neither series-parallel nor extremely small.     

基于联合法的配电网供电能力可靠性评估研究

分布式电源功率输出的随机性和间歇性及其并入电网的位置,会影响配网供电能力的可靠性.文中对此展开研究,首先建立了分布式电源、风电以及光伏发电三种数学模型,同时研究了负荷和系统可靠性指标概率分布特征,然后提出了一种将网络等值与拟蒙特卡罗联合法用于配电系统可靠性的定量评估,最后结合改进的IEEE-RBTS Bus6的F4馈线...     

Inflection points for network reliability

Given a finite, undirected graph G (possibly with multiple edges), we assume that the vertices are operational, but the edges are each independently operational with probability p. The (all-terminal) reliability, \(\operatorname{Rel}(G,p)\) , of G is the probability that the spanning subgraph of operational edges is connected. It has been conjectured that reliability functions have at most one point of inflection in (0,1). We show that the all-terminal reliability of almost every simple graph of order n has a point of inflection, and there are indeed infinite families of graphs (both simple and otherwise) with more than one point of inflection.     

多媒体网络可靠性分析系统实现

基于MDI的视频质量分析模型,设计并实现了多媒体网络可靠性分析系统。首先,基于RTP/RTCP协议,实现了多媒体网络视频的实时远程传输及播放。然后,将多媒体网络的视频主观评价方法与客观评价方法相结合,提出了一种综合可靠性评价方法,相较于目前的网络可靠性分析方法,综合可靠性评价方法更加全面、可信。最后,通过实验给出了可靠性分析系统的结果。     

Structural reliability of centralised tree network

An efficient algorithm is introduced for assigning a terminal as a centre in a tree network that makes the network reliable under a given reliability index. Some generalisation for multiple-centre assignment is provided.     

刍议计算机网络的可靠性提高措施

本文主要简单的介绍了计算机网络可靠性的相关内容,通过对影响计算机网络可靠性的因素进行分析,来探讨提高计算机网络可靠性的有效措施,以保障计算机网络的安全性。据此,有利于充分发挥计算机网络的功能,确保计算机网络的正常运行,降低计算机网络的安全风险,使其具有稳定性,提升我国计算机网络市场的竞争能力,从而推动我国计算机网络的可持续发展,为计算机网络的可靠性提供重要的保障。