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Research on Link Duration for Mobile Multihop Communication networks

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China Communications 2016年第8期13卷 159-168页

作者： Danyang Qin Shuang Jia Songxiang Yang Erfu Wang Qun Ding Key Laboratory of Electronics Engineering College of Heilongjiang University

Mobile multihop communication network is an important branch of modern mobile communication system, and is an important technical support for ubiquitous communication. The random movement of the nodes makes the networking be more flexible, but the frequently changing topology will decrease the link duration between nodes significantly, which will increase the packets loss probability and affect the network communication performance. Aiming at the problem of declining link duration caused by nomadic characteristics in mobile multihop communication network, four link duration models for possible moving states are established based on different features in real networking process in this paper, which will provide reliable criterion for the optimal routing selection. Model analysis and simulation results show that the reliable route established by the proposed model will effectively extend the link duration, and can enhance the global stability of the mobile multihop information transmission, so as to provide new option to transmission reliability improvement for the mobile communication network.

关键词： multihop mobile networks link duration network reliability node mobility models

reliability evaluation of wireless sensor networks using an enhanced OBDD algorithm

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 62-70页

作者： XIAO Yu-feng CHEN Shan-zhi LI Xin LI Yu-hong State Key Laboratory of networking and Switching Beijing University of Posts and Telecommunications Beijing 100876 China State Key Laboratory of Wireless Mobile Communication China Academy of Telecommunications Technology Beijing 100083 China Information Engineering School Southwest University of Science and Technology Mianyang 621000 China

An enhanced ordered binary decision diagram （EOBDD） algorithm is proposed to evaluate the reliability of wireless sensor networks （WSNs）, based on the considerations of the common cause failure （CCF） and a large number of nodes in WSNs. The EOBDD algorithm analyzes the common cause event （CCE） and the network structure when CCE takes place according to the stochastic graph and the CCF model of WSNs. After constructing the ordered binary decision diagram （OBDD） of the original network with node expansion, it uses a set of OBDD variables （SOV） to guide reliability computations along this OBDD. The two steps about OBDD can decrease the cost of OBDD constructions and storage. Furthermore, the efficient OBDD structure and Hash tables can greatly decrease redundant computations of isomorphs. The experiment results show that the EOBDD can be used to evaluate the reliability of WSN efficiently.

关键词： network reliability ordered binary decision diagram wireless sensor networks common cause failure common cause event

reliability and Feedback of Multiple Hop Wireless networks

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International Journal of Automation and computing 2007年第2期4卷 125-134页

作者： N. Eva Wu Sudha Thavamani Department of Electrical and Computer Engineering Binghamton UniversityBinghamtonNY 13902-6000USA

This paper analyzes fault-tolerance over the entire design life of a class of multiple-hop wireless networks, where cooperative transmission schemes are used. The networks are subject to both node failure and random channel fading. A node lifetime distribution is modeled with an increasing failure rate, where the node power consumption level enters the parameters of the distribution. A method for assessing both link and network reliabilities projected at the network＇s design life is developed. Link reliability is enhanced through use of redundant nodes. The number of redundant nodes is restricted by the cooperative transmission scheme used. The link reliability is then used to establish a re-transmission control policy that minimizes an expected cost involving power, bandwidth expenditures, and packet loss. The benefit and cost of feedback in network operations are examined. The results of a simulation study under specific node processing times are presented. The study quantifies the effect of loop closure frequency, acknowledgment deadline, and nodes＇ storage capacity on the performance of the network in terms of network lifetime, packet loss rate, and false alarm rate. The study concludes that in a network where energy is severely constrained, feedback must be applied judiciously.

关键词： Fault-tolerance network reliability energy efficiency packet loss rate discrete event simulation feedback optimal control.

A Genetic Algorithm to Solve Capacity Assignment Problem in a Flow network

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Computers, Materials & Continua 2020年第9期64卷 1579-1586页

作者： Ahmed Y.Hamed Monagi H.Alkinani M.R.Hassan Department of Computer Science Faculty of Computers and InformationSohag UniversitySohag82524Egypt Department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Department of Mathematics and Computer Science Faculty of ScienceAswan UniversityAswan81528Egypt

Computer networks and power transmission networks are treated as capacitated flow networks.A capacitated flow network may partially fail due to maintenance.Therefore,the capacity of each edge should be optimally assigned to face critical situations-i.e.,to keep the network functioning normally in the case of failure at one or more edges.The robust design problem(RDP)in a capacitated flow network is to search for the minimum capacity assignment of each edge such that the network still survived even under the edge’s failure.The RDP is known as NP-hard.Thus,capacity assignment problem subject to system reliability and total capacity constraints is studied in this paper.The problem is formulated mathematically,and a genetic algorithm is proposed to determine the optimal solution.The optimal solution found by the proposed algorithm is characterized by maximum reliability and minimum total capacity.Some numerical examples are presented to illustrate the efficiency of the proposed approach.

关键词： Flow network capacity assignment network reliability genetic algorithms

Computing the SKT reliability of Acyclic Directed networks Using Factoring Method

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Journal of Computer Science & Technology 1999年第1期14卷 56-63页

作者：孔繁甲王光兴 DepartmentofComputerScience NortheasternUniversityShengang110006PR.China DepartmentofComputerScien

This paper presents a factoring algorithm for computing source-to- K terminal (SKT) reliability, the probability that a source s can send message to a specified set of terminals K, in acyclic directed networks (AD-networks) in which both nodes and edges can fail. Based on Pivotal decomposition theorem, a new formula is derived for computing the SKT reliability of AD-networks. By establishing a topological property of AD-networks, it is shown that the SKT reliability of AD- networks can be computed by recursively applying this formula. Two new reliability- Preserving Reductions are also introduced. The recursion tree generated by the presented algorithm has at most 2 leaf nodes, where V and K are the numbers of nodes and terminals, respectively, while C is the number of the nodes satisfying some specified conditions. The computation complexity of the new algorithm is O (E. V. 2) in the worst case, where E is the number of edges. For source-to-all-terminal (SAT) reliability, its computation complexity is O(E). Comparison of the new algorithm with the existing ones indicates that the new algorithm is more efficient for computing the SKT reliability of AD-networks.

关键词： network reliability acyclic directed network factoring algorithm reliability-preserving reduction

Standardization Progress of Packet Transport networks

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ZTE Communications 2010年第3期8卷 5-8页

作者： Yang Jian Standard Development and Industry Relations Department Shenzhen 518057 P. R. China

Global operators are in the process of constructing next generation IP packet-switched networks, with the view of moving towards full IP-based networks. As data services increase, improvements in bandwidth, Quality of Service （QoS）, Operation Administration and Maintenance （OAM）, and network reliability are required. Convergence of network data transmission and network communications technology has been driven by converged IP services （including video, voice, and data）, and unified multi-service load demand. Packet Transport networking （PTN） has come into being to meet these requirements, and PTN Standards are being developing rapidly.

关键词： communications technology network reliability data transmission data services Maintenance of Service Operation Quality PTN voice video view come QoS OAM

A note on the bounded fragmentation graph

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A note on the bounded fragmentation graph