the paper deals with radio network distributed algorithms where initially no information about node degrees is available. We show that the lack of such an information affects the time complexity of existing fundamenta...
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ISBN:
(纸本)9783642113215
the paper deals with radio network distributed algorithms where initially no information about node degrees is available. We show that the lack of such an information affects the time complexity of existing fundamental algorithms by only a polylogarithmic factor. More precisely, given an n-node graph modeling a multi-hop radio network, we provide a O(log(2) n) time distributed algorithm that computes w.h.p., a constant approximation value of the degree of each node. We also provide a O(Delta log n + log(2) a) time distributed algorithm that computes will)., constant approximation value of the local maximum degree of each node, where the global maximum degree Delta of the graph is not known. Using our algorithm as a plug-and-play procedure, we show that the local maximum degree can be used instead of Delta to break the symmetry efficiently. We illustrate this claim by revisiting some fundamental algorithms that use Delta as a key parameter. First, we investigate the generic problem of simulating any point-to-point interference-free message passing algorithm in the radio network model. then, we study the fundamental coloring problem in unit disk graphs. the obtained results show that the local maximum degree allows nodes to self-organize in a local manner and to avoid the radio interferences from being a communication bottleneck.
BitTorrent ensures cooperation among peers through its inbuilt collaborative mechanisms, however due to lack of proper incentives, significant amount of free riding is observed in it. though in the existing literature...
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ISBN:
(纸本)9783642113215
BitTorrent ensures cooperation among peers through its inbuilt collaborative mechanisms, however due to lack of proper incentives, significant amount of free riding is observed in it. though in the existing literature, there exists some strategies to prevent free-riding, however, in case of large swarm sizes, it can be shown that they fail to stop free riding attempts effectively. To overcome this limitation, this paper presents a novel approach based on propagating the knowledge about the existence of possible free riders in the form of reputation among the peers within the swarm. It is shown, how a possible free riding attempt on a peer is reported to others and how tins knowledge is utilized in deciding whether to upload to a particular peer or not within a Bit Torrent swarm. Simulation results demonstrate how the proposed strategy effectively punishes free riders even in large swarm sizes.
Current network intrusion detection systems are lack of controllability, manifested as significant packet loss due to the long-term resources occupation by a single flow. the reasons can be classified into two kinds. ...
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A distributed algorithm is self-stabilizing if after faults and attacks hit the system and place it in some arbitrary global state, the system recovers from this catastrophic situation without external intervention in...
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ISBN:
(纸本)9783642113215
A distributed algorithm is self-stabilizing if after faults and attacks hit the system and place it in some arbitrary global state, the system recovers from this catastrophic situation without external intervention in finite time. Unidirectional networks preclude many common techniques in self-stabilization from being used, such as preserving local predicates. the focus of this work is on the classical vertex coloring problem, that is a basic building block for many resource allocation problems arising in wireless sensor networks. In this paper, we investigate the gain in complexity that can be obtained through randomization. We present a probabilistically self-stabilizing algorithm that uses k states per process, where k is a parameter of the algorithm. When k = Delta + 1, the algorithm recovers in expected O(Delta n) actions. When k may grow arbitrarily, the algorithm recovers in expected O(n) actions in total. thus, our algorithm can be made optimal with respect to space or time complexity. Our case study hints that randomization could help filling the complexity gap between bidirectionnal and unidirectionnal networks.
Recently, Genetic Algorithm has been studied as an effective approach for large scale optimization problems. However, we have issues of early convergence and settings of many parameters in the GA approach. In order to...
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Recently, Genetic Algorithm has been studied as an effective approach for large scale optimization problems. However, we have issues of early convergence and settings of many parameters in the GA approach. In order to deal with such issues, parameter free genetic algorithm(PfGA) and distributed genetic algorithm(DGA) were proposed. In this paper, we propose a distributed parameter free genetic algorithm(DPfGA) that keeps parameter free characteristic and improves efficiency of optimization. Besides the distributed construction of GA, we propose the method varying the number of offspring adaptively in accordance withthe current performance of optimization. We show effectiveness of the algorithm through application of the algorithm to TSP(Travelling Salesman Problem).
the proceedings contain 6 papers. the topics discussed include: practical implementation of blind synchronization in NC-OFDM based cognitive radio networks;cognitive spatial degrees of freedom estimation via compressi...
ISBN:
(纸本)9781450301411
the proceedings contain 6 papers. the topics discussed include: practical implementation of blind synchronization in NC-OFDM based cognitive radio networks;cognitive spatial degrees of freedom estimation via compressive sensing;a decentralized MAC for opportunistic spectrum access in cognitive wireless networks;energy-efficient communication in next generation rural-area wireless networks;spectrum occupancy validation and modeling using real-time measurements;and network coding relayed dynamic spectrum access.
Withthe development of the network technology, social network services(SNS), which are based on social network theory have gained increasing media, government and popular attention than ever before. In a social netwo...
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Error correction coding is being used on an almost routine basis in most communication systems including intelligent home networking. In addition, critical protocol management information requires high fidelity forwar...
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Error correction coding is being used on an almost routine basis in most communication systems including intelligent home networking. In addition, critical protocol management information requires high fidelity forward error correction (FEC) coding to ensure that the protocol functions correctly in the worst case situations. A powerful technique in the worst case situations is a Reed-Solomon (RS) code. Withthis technique, one achieves a high level of performance by trading an increase in overall block length for a reduction in hardware complexity. this paper concerns the design and implementation of RS codec for intelligent home networking. the 3 symbol error correcting RS codec is developed on field programmable gate array (FPGA) chips using very high speed integrated circuit hardware description language (VHDL). the logic functions are confirmed by VHDL simulator tool. the circuits are generated by the synthesis tool. Two FPGA chips are required and the FPGA utilization is 70% and 40%, respectively.
Enterprise distributed real-time and embedded (DRE) publish/subscribe (pub/sub) systems manage resources and data that are vital to users. Cloud computing-where computing resources are provisioned elastically and leas...
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ISBN:
(纸本)9783642169540
Enterprise distributed real-time and embedded (DRE) publish/subscribe (pub/sub) systems manage resources and data that are vital to users. Cloud computing-where computing resources are provisioned elastically and leased as a service-is an increasingly popular deployment paradigm. Enterprise DRE pub/sub systems can leverage cloud computing provisioning services to execute needed functionality when on-site computing resources are not available. Although cloud computing provides flexible on-demand computing and networking resources, enterprise DRE pub/sub systems often cannot accurately characterize their behavior a priori for the variety of resource configurations cloud computing supplies (e.g., CPU and network bandwidth), which makes it hard for DRE systems to leverage conventional cloud computing platforms. this paper provides two contributions to the study of how autonomic configuration of DRE pub/sub middleware can provision and use on-demand cloud resources effectively. We first describe how supervised machine learning can configure DRE pub/sub middleware services and transport protocols autonomically to support end-to-end quality-of-service (QoS) requirements based on cloud computing resources. We then present results that empirically validate how computing and networking resources affect enterprise DRE pub/sub system QoS. these results show how supervised machine learning can configure DRE pub/sub middleware adaptively in < 10 mu sec with bounded time complexity to support key QoS reliability and latency requirements.
the proceedings contain 15 papers. the topics discussed include: similarity analysis and modeling in mobile societies: the missing link;distributed stochastic optimization in opportunistic networks: the case of optima...
ISBN:
(纸本)9781450301398
the proceedings contain 15 papers. the topics discussed include: similarity analysis and modeling in mobile societies: the missing link;distributed stochastic optimization in opportunistic networks: the case of optimal relay selection;the state of DTN evaluation;cellular traffic offloading through opportunistic communications: a case study;locus: a location-based data overlay for disruption-tolerant networks;DTN routing in urban public transport systems;achieving anycast in DTNs by enhancing existing unicast protocols;a new mobility trace for realistic large-scale simulation of bus-based DTNs;dynamic, non-interactive key management for the bundle protocol;DTN experiments on the virtual meshtest testbed;making bundle protocol into a game;a relative time implementation for delay-tolerant networks.
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