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IEEE International Conference on Communications (ICC 2009)

作者： Si, JiangBo Li, Zan Liu, ZengJi Chen, XiaoJun Xidian Univ State Key Lab Integrated Serv Networks Xian 710071 Peoples R China

ISBN: (纸本)9781424434343

Minimizing the total transmission power is one of the main objectives of efficient broadcast algorithms in wireless networks, where all nodes are powered by battery with limited energy supply. Cooperative transmission is an important way to make full use of the space diversity and can save the transmission power significantly, especially in the wireless broadcast transmission, where the nodes can accumulate the overheard information. In this paper, firstly a centralized cooperative broadcast algorithm, which permits multiple nodes to cooperate in transmitting the broadcast message, is proposed to save the total transmission power. Considering that the centralized algorithm requiring a global knowledge of the networks is impractical in large wireless networks, the distributed version of the centralized algorithm requiring only 1-hop neighborhood information is proposed under the assumption that limited frequency band is available. The distributed algorithm combines the physical (PHY) and medium-access-control (MAC) layer mechanisms to reach all the nodes in a cooperative way. Though the proposed distributed algorithm is inferior to the centralized algorithm in terms of total transmission power, it takes less resource to broadcast than the centralized algorithms. Simulation results show that both the centralized algorithm and distributed algorithm can get a better performance than the existing broadcast algorithms. Furthermore, the distributed algorithm can achieve the total transmission power close to the centralized algorithm.

关键词： Cooperative Broadcasting Centralized algorithm Energy Efficient distributed algorithm

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EFFICIENT POWER UTILIZATION OF WIRELESS SENSOR NETWORKS: A SURVEY

EFFICIENT POWER UTILIZATION OF WIRELESS SENSOR NETWORKS: A S...

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International Conference on Advances in Recent Technologies in Communication and Computing

作者： Kori, Raveendra. H. Angadi, Adappa S. Hiremath, Manjunath Iddalagi, S. M. Basaveshwar Engn Coll Bagalkot Karnataka India

ISBN: (纸本)9781424451043

Recent advancement in wireless communications and electronics has enabled the development of low-cost & low power sensors networks. The sensor networks can be used for various application areas (e.g., health, military, home). Wireless Sensor Networks are autonomous devices forwarding locally collected data to a so-called sink node along multi-hop wireless paths. The main con-straint is the limited (battery) power. WSN are usually deployed in very harsh environment where node failure occurs frequently. The network should be resilient to node failure and should give long life which is of the order of 1-2 year with single charge. In this paper we have discussed some of the works done for efficient utilization of power in WSNs and some of the protocols, some of the coding and decoding algorithms used for power saving in WSNs has been discussed.

关键词： distributed algorithm clustering algorithm Iterative Channel Decoding algorithm OPERA and Address Coding Scheme

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Underlay Aware Resiliency in P2P Overlays

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10th International Conference on distributed Computing and Networking

作者： Kumar, S. D. Madhu Bellur, Umesh Govindan, V. K. Indian Inst Technol Dept Comp Sci & Engn Bombay 400076 Maharashtra India Natl Inst Technol Calicut Dept Comp Sci & Engn Calicut Kerala India

ISBN: (纸本)9783540922940

Modern distributed applications that run on P2P overlays need the overlay to be resilient to failures in the underlying communications network. An example application is that of event dissemination where the P2P overlay (the event broker network) delivers events published by a client to subscribers based on subscription filters. Achieving high availability requires that the overlay be aware of, and utilize the path redundancies in the underlying physical network. In addition, the overlay should be self organizing, as broker nodes may dynamically join or leave the network and centralized control is not an option in large scale networks. In this paper, we present Trimarg, an efficient distributed algorithm for achieving a self organizing overlay with an availability degree of three. Our algorithm is based on a graph theoretic foundation for highly available overlay networks and is designed to handle the concurrency issues of a large scale distributed system. The resulting unstructured P2P overlay ensures 3-degree of availability in the presence of node and link failures in the underlying physical network. We have proved the correctness of the algorithm and analyzed its complexity to show that the time complexity is O(diameter * degree)(2) of the network and the message complexity is O(diameter * degree). Our algorithm is the first of its kind to deal with concurrency issues and self organizing capabilities of the resultant overlay.

关键词： P2P overlays Event Broker Networks Availability distributed algorithm

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Construction and Maintenance of Overlays in Wireless Ad Hoc and Sensor Networks

Construction and Maintenance of Overlays in Wireless Ad Hoc ...

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作者：班亚米国立清华大学

学位级别：博士

无线传输技术与许多创新应用的快速发展，让无线随意式感测网路(wireless ad hoc and sensor networks, WASN)成为一门热门的研究领域。本论文探讨建构与维护WASN之叠加(overlay)结构的相关研究问题。所谓的叠加结构是在真实网路系统之... 详细信息

无线传输技术与许多创新应用的快速发展，让无线随意式感测网路(wireless ad hoc and sensor networks, WASN)成为一门热门的研究领域。本论文探讨建构与维护WASN之叠加(overlay)结构的相关研究问题。所谓的叠加结构是在真实网路系统之上的一种逻辑上的网路拓墣，其使用某些架构来连接网路内的一群结点。这些在叠加结构内的逻辑性网路连线，可以通过数个网路中的中介节点。在WASN中，研究者需探讨各种叠加结构(例如tree，mesh或cluster)于不同应用的情境(如flooding，gathering, multicasting与lookup等)之下的各种表现与状况。叠加结构将应用软体之下的实际网路架构做简化，将实际网路架构之复杂性、不规则性与一些不稳定的特性，做隐藏、简化性的描述。关于overlay的建构，我们探讨研究在静态性的WASN上建构ring形式的叠加结构。所谓的ring形式的叠加结构是将网路内的节点用ring将其串起，如同Hamiltonian cycle一样。在随意图形上建构Hamiltonian cycle是非常困难的。我们研究实际的问题，例如可靠性的档案传输，互斥问题与时间同步问题，结果显示ring架构确实有办法可以解决上述问题。我们所提出的ring形式的叠加结构有支援multiple nodes appearance (overlay的路径可以通过同一节点一次以上。)，同时架构内允许side-path与loop。Ring形式的overlay可以让节点进行双向且无碰撞的讯息传输，进行节点排序，且提供进行网路操作之后的节点状况回报，而且这些回报资讯是不需额外讯息成本的。我们探讨各种不同的ring形式overlay的分散式建构演算法与其最佳化的相关问题。于overlay的维护上，我们探讨于丛集式行动随意型网路(Cluster-based Mobile ad hoc network, cluster-based MANET)的资源维护相关问题。我们考量使用cluster-head来进行资源管理，我们称为Cluster-Based With Head Overlay (CWHO)。使用head node这种方法所会衍生出之某些问题，例如节点失效与hotspot(少数节点流量过高)、资源消耗过高等情况，我们提出了一种完全分散性的资源管理机制，称为Cluster-Based WithOut Head Overlay (CWOHO)。在CWOHO，我们将所有节点的资源分散到cluster之中，使得每一个节点都可以变成cluster head。CWHO与CWOHO都是进行全面性维护(total maintenance)，每个cluster都可以维护在网路中所有cluster的资讯。此种全面性维护之要求，对于某些讯息传输延迟有要求与限制的应用情境，例如多媒体的应用，是种不可或缺的特性。除了此两种极端性的策略，我们讨论第三种维护策略，称为Clusters with Neighbor Information (CNI)。以上三种策略的表现都有进行评估与比较。

关键词： overlay wireless sensor network routing ring distributed algorithm Ad hoc networks

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Selfishness-Aware Data-driven Overlay Network

Selfishness-Aware Data-driven Overlay Network

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IEEE Global Telecommunications Conference (GLOBECOM 09)

作者： Wang, Miao Zhang, Yujun Li, Guojie Chinese Acad Sci Inst Comp Technol Beijing 100190 Peoples R China

ISBN: (纸本)9781424441471

Data-driven overlay network (DONet) especially works well with live-event streaming because data can be propagated in a relatively continuous way even with node dynamics. However, optimal streaming demands the cooperation of individual nodes. In the real world, some selfish participants which might delay forwarding or stop forwarding data can affect the overall streaming quality. To address the selfishness issue, we propose a selfishness-aware DONet (SA-DONet) in this paper. SA-DONet allows each node associative with an altruism value for its contributions to peers. Based on the altruism value, segment requesting and sending algorithms are designed to ensure the more altruistic nodes will have more chances to be served. The primary characteristic of our mechanism lies in three aspects. Firstly, SA-DONet can discover the selfish nodes in a decentralized manner and adjust the segment sending and requesting strategy dynamically. Secondly, selfish assessment (altruism value) comes from the node's history and doesn't require any extra probe and measuring packets. Lastly, our algorithms remain comparable computing complexity to DONet. Simulation results show that compared with DONet, even with a significant portion of nodes being selfish, SA-DONet can improve the streaming quality of global multicast session with low control overhead.

关键词： altruism value application-layer multicast data-driven distributed algorithm selfishness

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Centralized and distributed algorithms for Routing and Weighted Max-Min Fair Bandwidth Allocation

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IEEE-ACM TRANSACTIONS ON NETWORKING 2008年第5期16卷 1015-1024页

作者： Allalouf, Miriam Shavitt, Yuval Tel Aviv Univ Dept Elect Engn Syst Sch Elect Engn IL-69978 Ramat Aviv Israel

Given a set of demands between pairs of nodes, we examine the traffic engineering problem of flow routing and fair bandwidth allocation where flows can be split to multiple paths (e.g., MPLS tunnels). This paper presents an algorithm for finding an optimal and global per-commodity max-min fair rate vector in a polynomial number of steps. In addition, we present a fast and novel distributed algorithm where each source router can find the routing and the fair rate allocation for its commodities while keeping the locally optimal max-min fair allocation criteria. The distributed algorithm is a fully polynomial epsilon-approximation (FPTAS) algorithm and is based on a primal-dual alternation technique. We implemented these algorithms to demonstrate its correctness, efficiency, and accuracy.

关键词： Bandwidth allocation distributed algorithm max-min fairness criteria maximum concurrent multi-commodity flow problem

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A distributed AOA Based Localization algorithm for Wireless Sensor Networks

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JOURNAL OF COMPUTERS 2008年第4期3卷 1-8页

作者： Di Stefano, Gabriele Petricola, Alberto Univ Laquila Elect & Informat Engn Dept Laquila Italy

In this paper we propose a distributed algorithm for solving the positioning problem in ad-hoc wireless networks. The method is based on the capability of the nodes to measure the angle of arrival (AOA) of the signals they produce. The main features of the distributed algorithm are simplicity, asynchronous operations (i.e. no global coordination among nodes is required), ability to operate in disconnected networks. Moreover each node can join the computation at any time. Numerical results, obtained by simulating several scenarios, show that the algorithm can reach a good level of convergence even when the number of communications is limited.

关键词： distributed algorithm sensor networks angle of arrival

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3D face recognition with wireless transportation

3D face recognition with wireless transportation

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作者： Zou, Le Texas A&M University

In this dissertation, we focus on two related parts of a 3D face recognition system with wireless transportation. In the ﬁrst part, the core components of the system, namely, the feature extraction and classiﬁcation component, are introduced. In the feature extraction component, range images are taken as inputs and processed in order to extract features. The classiﬁcation component uses the extracted features as inputs and makes classiﬁcation decisions based on trained classiﬁers. In the second part, we consider the wireless transportation problem of range images, which are captured by scattered sensor nodes from target objects and are forwarded to the core components (i.e., feature extraction and classiﬁcation components) of the face recognition system. Contrary to the conventional deﬁnition of being a transducer, a sensor node can be a person, a vehicle, etc. The wireless transportation component not only brings ﬂexibility to the system but also makes the “proactive” face recognition possible. For the feature extraction component, we ﬁrst introduce the 3D Morphable Model. Then a 3D feature extraction algorithm based on the 3D Morphable Model is presented. The algorithm is insensitive to facial expression. Experimental results show that it can accurately extract features. Following that, we discuss the generic face warping algorithm that can quickly extract features with high accuracy. The proposed algorithm is robust to holes, facial expressions and hair. Furthermore, our experimental results show that the generated features can highly diﬀerentiate facial images. For the classiﬁcation component, a classiﬁer based on Mahalanobis distance is introduced. Based on the classiﬁer, recognition performances of the extracted features are given. The classiﬁcation results demonstrate the advantage of the features from the generic face warping algorithm. For the wireless transportation of the captured images, we consider the location-based wireless sensor networks (WSN). I

关键词： Face recognition Feature extraction Three-dimensional vision Digital Image Processing Image Classification 3D model distributed algorithm Graph theory Protocols Routing Sensor networks Shortest path Topology Book Thesis

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distributed multichannel power allocation algorithm for spectrum sharing cognitive radio networks

Distributed multichannel power allocation algorithm for spec...

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IEEE Wireless Communications and Networking Conference

作者： Wu, Yuan Tsang, Danny H. K. Hong Kong Univ Sci & Technol Dept Elect & Comp Engn Hong Kong Hong Kong Peoples R China

ISBN: (纸本)9781424419968

In this paper, we study the distributed multichannel power allocation (MCPA) problem for the spectrum sharing cognitive radio networks (CRNs), where secondary transceiver pairs share the same spectrum with the primary system. The problem is formulated as a non-cooperative game with coupled constraints to address the interference temperature restrictions imposed by the primary system. Existence and uniqueness of the Nash Equilibrium (N.E.) for this coupled constraints MCPA game are investigated. distributed MCPA algorithm is proposed to approach the unique N.E. Simulation results are obtained to verify the validity of the proposed algorithm.

关键词： cognitive radio power allocation non-cooperative game coupled constraint distributed algorithm

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A distributed algorithm for the dead end problem of location based routing in sensor networks

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2005年第4期54卷 1509-1522页

作者： Zou, L Lu, M Xiong, ZX Texas A&M Univ Dept Elect Engn College Stn TX 77843 USA

The dead end problem in greedy forwarding is an important issue of location based routing in sensor networks. It occurs when a message falls into a local minimum using greedy forwarding. Current solutions to this problem are insufficient in either eliminating traffic/path memorization or finding satisfactory short paths. In this paper, we propose a novel algorithm, called partial-partition avoiding geographic routing (PAGER), to solve the problem. The basic idea of PAGER is to divide a sensor network graph into functional subgraphs and provide each sensor node with message forwarding directions based on these subgraphs. PAGER results in loop free short paths without memorization of traffics/paths in sensor nodes. It does not require planarization of the underlying network graph. Further, the mobility adaptability of PAGER makes it suitable for use in mobile sensor networks with frequent topology changes. We implement the PAGER algorithm in two protocols and evaluate them in sensor networks with different parameters. Experimental results show the advantage of PAGER in the context of sensor networks.

关键词： distributed algorithm graph theory protocols routing sensor networks shortest path topology

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