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作者： Fashandi, Shervan University of Waterloo

学位级别：master

Recently, erasure networks have received significant attention in the literature as they are used to model both wireless and wireline packet-switched networks. Many packet-switched data networks like wireless mesh networks, the Internet, and Peer-to-peer networks can be modeled as erasure networks. In any erasure network, path diversity works by setting up multiple parallel connections between the end points using the topological path redundancy of the network. Our analysis of diversity over erasure networks studies the problem of rate allocation (RA) across multiple independent paths, coding over erasure channels, and the trade-off between rate and diversity gain in three consecutive *** the chapter 2, Forward Error Correction (FEC) is applied across multiple independent paths to enhance the end-to-end reliability. We prove that the probability of irrecoverable loss (P_E) decays exponentially with the number of paths. Furthermore, the RA problem across independent paths is studied. Our objective is to find the optimal RA, i.e. the allocation which minimizes P_E. Using memoization technique, a heuristic suboptimal algorithm with polynomial runtime is proposed for RA over a finite number of paths. This algorithm converges to the asymptotically optimal RA when the number of paths is large. For practical number of paths, the simulation results demonstrate the close-to-optimal performance of the proposed algorithm. Chapter 3 addresses the problem of lower-bounding the probability of error (PE) for any block code over an input-independent channel. We derive a lower-bound on PE for a general input-independent channel and find the necessary and sufficient condition to meet this bound with equality. The rest of this chapter applies this lower-bound to three special input-independent channels: erasure channel, super-symmetric Discrete Memoryless Channel (DMC), and q-ary symmetric DMC. It is proved that Maximum Distance Separable (MDS) codes achieve the minimum probab

关键词： Erasure networks Diversity Routing Internet linear network coding Diversity-rate trade-off Path diversity rate allocation MDS codes Forward error correction

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WSN4QoL: A WSN-Oriented Healthcare System Architecture

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INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR networkS 2014年第5期10卷 1-16页

作者： Tennina, S. Di Renzo, M. Kartsakli, E. Graziosi, F. Lalos, A. S. Antonopoulos, A. Mekikis, P. V. Alonso, L. Univ Aquila WEST Aquila Srl I-67100 Laquila Italy CNRS Supelec F-91192 Paris France Tech Univ Catalunya UPC Dept SignalTheory & Commun TSC Barcelona 08034 Spain CTTC Barcelona 08860 Spain

People worldwide are getting older and this fact has pushed the need for designing new, more pervasive, and possibly cost effective healthcare systems. In this field, distributed and networked embedded systems, such as wireless sensor networks (WSNs), are the most appealing technology to achieve continuous monitoring of aged people for their own safety, without affecting their daily activities. This paper proposes recent advancements in this field by introducing WSN4QoL, a Marie Curie project which involves academic and industrial partners from three EU countries. The project aims to propose new WSN-based technologies to meet the specific requirements of pervasive healthcare applications. In particular, in this paper, the system architecture is presented to cope with the challenges imposed by the specific application scenario. This includes a network coding (NC) mechanism and a distributed localization solution that have been implemented on WSN testbeds to achieve efficiency in the communications and to enable indoor people tracking. Preliminary results in a real environment show good system performance that meet our expectations.

关键词： HEALTH facilities WIRELESS sensor networks MEDICAL technology linear network coding DISTRIBUTED sensors

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Faulty Line Selection Method for Distribution network Based on Variable Scale Bistable System

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JOURNAL OF SENSORS 2016年第9-6期2016卷 1-17页

作者： Wang, Xiaowei Gao, Jie Song, Guobing Cheng, Qiming Wei, Xiangxiang Wei, Yanfang Xi An Jiao Tong Univ Sch Elect Engn Xian 710049 Shaanxi Provinc Peoples R China Shanghai Univ Elect Power Coll Automat Engn Shanghai Peoples R China China Agr Univ Coll Informat & Elect Engn Beijing Peoples R China Henan Polytech Univ Sch Elect Engn & Automat Jiaozuo 454000 Peoples R China

Since weak fault signals often lead to the misjudgment and other problems for faulty line selection in small current to ground system, this paper proposes a novel faulty line selection method based on variable scale bistable system(VSBS). Firstly, VSBS is adopted to analyze the transient zero-sequence current (TZSC) with different frequency variety scale ratio and noise intensity, and the results show that VSBS can effectively extract the variation trends of initial stage of TZSC. Secondly, TZSC is input to VSBS for calculation with Runge-Kutta equations, and the output signal is chosen as the characteristic currents. Lastly, correlation coefficients of every line characteristic current are used as the index to a novel faulty line selection criterion. A large number of simulation experiments prove that the proposed method can accurately select the faulty line and extract weak fault signals in the environment with strong noise.

关键词： linear network coding System failures (Engineering) Bistable devices Distribution (Probability theory) Runge-Kutta formulas

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A Game-Theoretic Analysis of Multiple Protocol Data Flows in Hierarchical M2M Communication networks

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INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR networkS 2013年第11期9卷 1-8页

作者： Wang, Gang Leng, Jie Bai, Lin Beihang Univ Sch Elect & Informat Engn Beijing 100191 Peoples R China

A hierarchical machine-to-machine (M2M) communication network, where multiple heterogeneous devices compete for transmission on congested links, is considered. In such a network, the cluster headers gather the network coding and routing messages from multiple M2M devices and forward them to the cellular network. We propose a novel discriminatory user-based utility mechanism for network coding users and routing users. The price of anarchy (PoA), which is used to characterize the worst-case efficiency bounds, is analyzed. The simulation results show that network coding could promote the efficiency to a certain extent.

关键词： DATA flow computing MACHINE-to-machine communications linear network coding CELLULAR neural networks (Computer science) ROUTING (Computer network management)

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Distributed Dynamic Memetic Algorithm Based coding Aware Routing for Wireless Mesh Sensor networks

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INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR networkS 2016年第3期12卷 5429303-5429303页

作者： Hamam, Saeed Almogren, Ahmad S. King Saud Univ Coll Comp & Informat Sci Dept Comp Sci Riyadh 11543 Saudi Arabia

network coding has been confirmed as a potential technology to improve performance of wireless mesh networks (WMNs);network coding has great advantages for sensor networks like minimization of communication needed to collect sensor data and error recovery. A few network coding aware routings have been proposed. However, these mechanisms detect coding opportunities through local traffic pattern checking, which hardly obtains optimal routes. This paper proposes a Distributed Dynamic Memetic Algorithm Based coding Aware Routing (DDMCAR) for wireless mesh networks, which employs memetic algorithm to optimize routes and coding opportunities. This paper proposes an improvement over GCAR algorithm by employing memetic algorithm and also meme sharing among nodes to increase the chance of finding optimal solution and continuous monitoring and update of meme fitness to achieve a dynamic tracking of network conditions, and finally using most fit memes for load balancing elevating congestion. Through simulations on randomly generated wireless mesh networks, DDMCAR is to be shown to find optimal routes within a short time and achieve more improvements than GCAR.

关键词： WIRELESS mesh networks COMPUTER algorithms linear network coding ERROR analysis (Mathematics) TRAFFIC patterns

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Side Trip Multipath Routing Protocol for Spatial Node Failure in Data-Gathering WSNs

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INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR networkS 2016年第4期2016卷 9161625-9161625页

作者： Fujita, Keisuke Takaki, Yumi Ohta, Chikara Tamaki, Hisashi Kobe Univ Grad Sch Syst Informat Nada Ku Rokkodai Cho 1-1 Kobe Hyogo 6578501 Japan

In severe disaster environments, data-gathering wireless sensor networks possibly suffer from spatial node failure due to external factors such as land slide and river overflow. In order to enhance tolerance to spatial node failure, this paper proposes not only a multipath data gathering protocol called "Side Trip (ST)" scheme but also an improved version of ST scheme called " Side Trip with network coding (STNC)" scheme. In the ST scheme, a node establishes a secondary path which passes through nodes almost the same hop count away from the sink in order to spatially separate the path from the primary path and enhance spatial node-failure tolerance. In the STNC scheme, redundant packets from different source nodes are network-coded into an encoded packet in order to reduce the number of redundant packets and the impact on the system lifetime. We compare the ST scheme, STNC scheme, and two existing multipath protocols (i.e., H-SPREAD (Hybrid-Secure Protocol for REliable dAta Delivery) scheme and SMRP (Subbranch Multipath Routing Protocol) scheme) by means of a self-developed simulator. Simulation results show that STNC scheme and ST scheme enhance tolerance to node-failure compared to H-SPREAD scheme and SMRP scheme with no significant impact on system lifetime.

关键词： ROUTING protocols (Computer network protocols) WIRELESS sensor networks ACQUISITION of data linear network coding DATA packets & packeting TOLERANCE analysis (Engineering)

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The Performance of Multimessage Algebraic Gossip in a Random Geometric Graph

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INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR networkS 2013年第12期9卷 1-7页

作者： Wang, Gang Lin, Zun Guan, Wenyang Wang, Feng Beihang Univ Sch Elect & Informat Engn Beijing Peoples R China Peking Univ Sch Elect Engn & Comp Sci Beijing 100871 Peoples R China Commercial Aircraft Corp China Beijing Aeronaut Sci & Technol Res Inst Beijing Peoples R China

Gossip algorithm has been widely regarded as a simple and efficient method to improve quality of service (QoS) in large-scale network which requires rapid information dissemination. In this paper, information dissemination based on algebraic gossip in a random geometric graph (RGG) is considered. The n nodes only have knowledge about their own contents. In every time slot, each node communicates with a neighbor partner chosen randomly. The goal is to disseminate all of the messages rapidly among the nodes. We show that the gain of the convergence time is O(n(1/2) log epsilon(-1) /log(1/2)n) with network coding. Simulation results show that these bounds are valid for the random geometric graph and demonstrate that network coding significantly improves the bounds with the number of users increasing.

关键词： RANDOM graphs QUALITY of service INFORMATION dissemination linear network coding TELECOMMUNICATION systems -- Management

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A novel secure coding-based approach for multi-cast transmission

A novel secure coding-based approach for multi-cast transmis...

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IEEE International Conference on High Performance Computing and Communications

作者： Zuoting Ning Dafang Zhang Kun Xie Xiaan Bi College of Computer Science and Electronic Engineering Hunan University Changsha 410082 P. R. China College of Mathematics and Computer Science Hunan Normal University Changsha 410081 P. R. China

ISBN: (纸本)9781509042982

A lot of research shows that network coding can significantly improve the performance of multi-cast transmission. However, due to the inherent disadvantage of network coding, it is very vulnerable to pollution attacks in which adversaries can inject bogus data. Moreover, those bogus data will be used with legitimate data at the downstream nodes, resulting in the failure of decoding original data as well as a sharp decrease of the network performance. In this paper, we propose a novel approach to identify pollution attacks, so that malicious nodes can be rapidly identified and isolated from the networks. In our scheme, in order to prevent malicious attacks, we design a secure infrastructure in which we exploit key pre-distribution and Message Authentication Codes(MACs);Meanwhile, we propose a secure transmission protocol. Each node registers a key from center server and appends MACs to each packet. Furthermore, in order to make verification, each node needs to carry out hash computation for every incoming packet under the secure transmission protocol. Experimental results demonstrate that our scheme has practical advantages in the presence of end-to-end delay, network throughput and identification delay.

关键词： Pollution attack Malicious nodes linear network coding Multi-cast

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The Exact Outage Probability of Multiuser linear network Coded Cooperation System

The Exact Outage Probability of Multiuser Linear Network Cod...

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IEEE Global Communications Conference

作者： Zhenzhou Tang Hongyu Wang Qian Hu Xiaoqiu Shi College of Physics and Electronic Information Engineering Wenzhou University School of Information and Communication Engineering Dalian University of Technology

ISBN: (纸本)9781479935130

Outage probability is one of the most important performance measures for cooperative communication systems. And the closed-form solution on exact outage probability is essential for many further studies, such as optimal power allocation and rate control. However, as far as we know, the issue remains open for multiuser linear network coded cooperation (LNCC), which is a technology integrating linear network coding into cooperative communication. Consequently, in this paper, we investigate the multiuser LNCC system with multiple cooperation time slots and many-to-one communication pattern. All the possible outage scenarios are fully considered and the closed-form solution of the system's exact outage probability is theoretically derived. In order to obtain the diversity order of the LNCC system, the asymptotic outage probability is also analysed. The theoretical analyses are verified by plenty of Monte Carlo simulations. In order to demonstrate the benefits introduced by LNC to the cooperative system, the outage performance comparison between the LNCC and the traditional Decode-and-Forward (DF) cooperation system is carried out. The results show that given the same number of users and cooperation time slots, the LNCC system's outage probability is greatly lower than that of the traditional DF cooperation system.

关键词： Monte Carlo methods cooperative communication decode and forward communication network coding probability Monte Carlo simulations asymptotic outage probability closed-form solution cooperative communication systems decode-and-forward cooperation system exact outage probability linear network coding multiuser linear network coded cooperation system Closed-form solutions Cooperative communication Cooperative systems Educational institutions network coding Signal to noise ratio

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Diversity-Rate Trade-off in Erasure networks

Diversity-Rate Trade-off in Erasure Networks

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2010 Proceedings IEEE INFOCOM

作者： Shahab Oveis Gharan Shervan Fashandi Amir K. Khandani ECE Dept. University of Waterloo Waterloo ON Canada N2L3G1

ISBN: (纸本)9781424458363

This paper addresses a fundamental trade-off between rate and the diversity gain of an end-to-end connection in an erasure network. The erasure network is modeled by a directed graph whose links are orthogonal erasure channels. Furthermore, the erasure network is assumed to be nonergodic, meaning that the erasure status of the links are assumed to be fixed during each block of transmission and change independently from block to block. The erasure status of the links is assumed to be known only by the destination node. First, we study the homogeneous erasure networks in which the links have the same erasure probability and capacity. We derive the optimum trade-off between diversity gain and the end-to-end rate and prove that a variant of the conventional routing strategy combined with an appropriate forward error correction at the end-nodes achieves the optimum diversity-rate tradeoff. Next, we consider the general erasure networks in which different links may have different values of erasure probability and capacity. We prove that there exist general erasure networks for which any conventional routing strategy fails to achieve the optimum diversity-rate trade-off. However, for any general erasure graph, we show that there exists a linear network coding strategy which achieves the optimum diversity-rate trade-off. Unlike the previous works which suggest the potential benefit of linear network coding in the error-free multicast scenario (in terms of the achievable rate), our result introduces the benefit of linear network coding in the erasure single-source single-destination scenario (in terms of the diversity gain). Finally, we study the diversity-rate trade-off through simulations. The erasure graphs are constructed according to the Barabasi-Albert random model which is known to capture the scale-free property of the practical packet switched networks like the Internet. The error probability is depicted for different network strategies and different rate values. Th

关键词： Erasure networks Diversity Routing Internet linear network coding Diversity-rate trade-off

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