By Topic

Advances in Mesh Networks (MESH), 2010 Third International Conference on

Date 18-25 July 2010

Filter Results

Displaying Results 1 - 25 of 29
  • [Front cover]

    Page(s): C1
    Save to Project icon | Request Permissions | PDF file iconPDF (831 KB)  
    Freely Available from IEEE
  • [Title page i]

    Page(s): i
    Save to Project icon | Request Permissions | PDF file iconPDF (11 KB)  
    Freely Available from IEEE
  • [Title page iii]

    Page(s): iii
    Save to Project icon | Request Permissions | PDF file iconPDF (58 KB)  
    Freely Available from IEEE
  • [Copyright notice]

    Page(s): iv
    Save to Project icon | Request Permissions | PDF file iconPDF (109 KB)  
    Freely Available from IEEE
  • Table of contents

    Page(s): v - vi
    Save to Project icon | Request Permissions | PDF file iconPDF (168 KB)  
    Freely Available from IEEE
  • Preface

    Page(s): vii
    Save to Project icon | Request Permissions | PDF file iconPDF (54 KB)  
    Freely Available from IEEE
  • Organizing Committee

    Page(s): viii - ix
    Save to Project icon | Request Permissions | PDF file iconPDF (87 KB)  
    Freely Available from IEEE
  • list-reviewer

    Page(s): x
    Save to Project icon | Request Permissions | PDF file iconPDF (62 KB)  
    Freely Available from IEEE
  • The Achievable Cell Capacity in Cellular Wireless Mesh Networks

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (183 KB) |  | HTML iconHTML  

    We envision a future ubiquitous wireless access network called a cellular wireless mesh network. A cellular wireless mesh network is organized in multi-radio, multi-channel, multi-rate and multi-hop radio cells, each served by a single gateway. We propose the Maximum Channel Collision Time algorithm, which derives an expression for a conservative cell capacity. We prove that the conservative cell capacity is achievable and thus name it the achievable cell capacity. We validate our results with ns-2 simulations. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance Evaluation of AODV and OLSR-Meshed IP-Enabled IEEE802.15.4

    Page(s): 7 - 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (352 KB) |  | HTML iconHTML  

    Safety critical applications of IEEE 802.15.4 networks require autonomous network reconfiguration and dynamic meshing in case of node failures or changing environmental influences. In contrast to the classical approach of wireless sensor networks, this paper focuses on the development of enhanced network services like multimedia transmissions in a gas concentration monitoring scenario. Therefore, this paper demonstrates the application of Ad hoc On Demand Distance Vector (AODV) and Optimized Link State Routing (OLSR) on IEEE 802.15.4 nodes based on an IP layer-instead of relying on the standard ZigBee configuration. The new network configuration is evaluated for handover processes between mobile and stationary nodes. The time delay, maximum throughput and generated overhead is compared between the two routing protocols for different node constellations. Finally, the lifetime of the node is evaluated in comparison to the ordinary IEEE 802.15.4 configuration and IEEE 802.11. Concluding, the application of AODV and OLSR for power-constrained IEEE 802.15.4 nodes is proposed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Experimental Procedure for the Characterization and Optimization of the Power Consumption and Reliability in ZigBee Mesh Networks

    Page(s): 13 - 16
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (824 KB) |  | HTML iconHTML  

    In this paper, a study of the behavior of wireless mesh networks is proposed, by considering energy consumption and reliability of the network. The real consumption with different network topologies and different data profiles will be analized. The objective of this work is to establish the framework to carry out energy optimizations in order to reduce the energy consumption without losing the reliability and efficiency of the network. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Self-Organizing Mobile Mesh Networks with Peer-to-Peer Routing and Information Search Services

    Page(s): 17 - 22
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (653 KB) |  | HTML iconHTML  

    The work presents a decentralized protocol that allows self-organization of autonomous wireless devices in mobile mesh networks. In the resulting infrastructure the routing and information services are provided in a peer-to- peer fashion. Both services are performed through multi- hop radio transmissions among participant nodes with no fixed infrastructure required and avoiding to use broadcast of messages. Since links among nodes may be continuously destroyed and created, as a consequence of nodes movement and/or variations in connectivity range (e.g. due to temporary obstacles), our protocol is based on virtual network addresses which are dynamically assigned to groups of nodes (called islands). Routing requests are performed through unicast transmissions when traveling among islands and exploiting wireless overhearing when involving members of the same island (in- island routing). We will demonstrate that assigning virtual coordinates to groups of nodes guarantees network flexibility with a reasonable amount of overheard and that the amount of radio transmissions required is scalable with the number of nodes. Simulations have shown that the proposed solution can generate reliable networks, despite the unpredictable topology, assuming the use of devices with common radio range connectivity moving at pedestrian velocity. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Altruistic Traffic Limits Computation in Wireless Broadcast Networks

    Page(s): 23 - 27
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (518 KB) |  | HTML iconHTML  

    The statistical behavior of wireless medium access can generally be described by a function that relates the offered traffic to the collision probability and delay. Given a maximum tolerable collision probability and/or delay (quality-of-service constraints), one can derive the maximum admissible offered traffic for a given medium access strategy. In this paper, we describe both a centralized as well as a distributed algorithm that can, for an arbitrary connectivity configuration, compute the maximum traffic that may be sourced into the network by any network node under the constraint that the maximum offered traffic condition is met at any node. We demonstrate that both algorithms achieve significant improvements for most networks compared to a static maximum traffic assignment. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Simulation-Based Optimization for Wireless Mesh Network Planning

    Page(s): 28 - 34
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (347 KB) |  | HTML iconHTML  

    Wireless mesh networks are dynamically self-organized and self-configured, with the nodes in the network automatically establishing and maintaining mesh connectivity among them. Wireless mesh networks consist of three types of nodes: clients, routers and gateways. Wireless Mesh Network planning consists of determining the amount of routers needed to meet the demands for Internet access. It is a complicated task since it involves several sets of variables: network topology, traffic model, cost, capability etc. In this paper, we developed a simulation tool for planning of wireless mesh networks, which routers must be installed and the routes between clients and gateways are chosen using optimization metrics. We developed the simulator based on a mathematical model proposed for the problem, using the optimization metrics of the model. Thus, in this paper, we define specific scenarios for comparing simulation results with the results obtained with the mathematical model. The simulator finds good solutions and it is able to simulate large networks. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of Emergency Message Transmission Delays in Vehicular Wireless Mesh Network

    Page(s): 35 - 40
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (893 KB) |  | HTML iconHTML  

    Road accidents and traffic jams are the most important problems on the roads. Wireless Access in Vehicular Environments (WAVE) can be used as preemptive and informational measure. WAVE builds multi-path communication between vehicles and infrastructure nodes, where nodes share emergency and other information. In this paper we analyze the delay of emergency message transmission in multi-hop link, based on IEEE 802.11 and draft IEEE 802.11p. Simulations in NCTUns 5.0 environment show that single message propagation is in permissible range even for 100 nodes. Several scenarios simulated show that trade-off between reliability and message delivery latency exists. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multihop Interference and Multihop Propagation of Control Signaling in IEEE 802.16d Mesh Networks

    Page(s): 41 - 47
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (285 KB) |  | HTML iconHTML  

    As defined in the mesh mode of the IEEE 802.16d specifications, one of the functions control signaling does is scheduling of transmissions among nodes. A node wanting to transmit has to check that no other transmissions are happening around the intended receiving node; and that no receptions are happening around the transmitting node. In other words, the node wanting to transmit has to know the status of nodes in its two-hop neighborhood. The mesh election algorithm is used for coordination of transmissions for control signaling; the three-way-handshake signaling is used for coordination of data transmissions. However, transmissions from nodes further than two hops away could still cause interference. To reduce this interference from nodes more than two hops away, the transmission scheduling mechanism and signaling can be made to include these further-away nodes. The expanded-signaling and extended-signaling schemes are presented to achieve this. Simulations show that the extended-signaling scheme reduces interference-caused packet losses while achieving good packet reception ratio. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Realistic Beamforming Model for ns-2

    Page(s): 48 - 52
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (300 KB) |  | HTML iconHTML  

    We present an extension to network simulator ns-2 for simulation of smart antennas with maximize gain beamforming. Unlike some of the previous work on this topic, we use a realistic beamforming model with detailed radiation patterns. Our antenna framework can be used to evaluate the characteristics of beamforming under various conditions and can be combined with any MAC protocol with smart antenna interface. Exemplary, we implemented two MAC protocols, and results show that with beamforming overall throughput and packet delay can be improved. The magnitude of this improvement is of course dependent on the chosen protocol and scenario. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bayesian VoIP Quality Evaluation Using the Time Between Retried Calls

    Page(s): 53 - 58
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (380 KB) |  | HTML iconHTML  

    This paper presents a new method for determining the voice quality of a VoIP carrier at a given time. The current methods rely on the voice stream analysis, their main drawback being the large computational power required and the cost for licenses. The method presented in this paper analyses the time difference between successive calls from the same source number to the same destination number, and identifies a connection between this calling pattern and the voice quality of a VoIP carrier. The advantage of this method relies in its low computational power requirement, as the voice stream analysis is no longer required. Bayesian networks are built to infer the exact a posteriori probability of poor voice quality. A case study was performed on a prepaid long distance carrier and the results show that a large percent (above 50%) of the customer complaints can be identified using this method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Mobility-Aware Hybrid Routing Approach for Wireless Mesh Networks

    Page(s): 59 - 62
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (240 KB) |  | HTML iconHTML  

    Wireless mesh networks (WMNs) are attractive as a new communication paradigm. Ad hoc routing protocols for WMNs are classified into: (a) proactive, (b) reactive, and (c) hybrid approaches. In general, proactive routing is more suitable for a stationary network, while reactive routing is better for a mobile network with a high mobility. In many applications, a node in WMN is mobile but it can fluctuate between being mobile and being stationary. Therefore, a hybrid routing approach with the ability to adapt to node mobility could improve the performance of WMNs. In this paper, we propose a Mobility-aware Hybrid Routing (MHR) approach for WMNs, which varies its routing between reactive and proactive to adapt to node mobility. The MHR basically uses a reactive approach for route discovery, and as a proactive approach it maintains the route entry in the routing table unless the route fails due to node movement, even if the route is not used. In this paper, the MHR approach was applied to AODV, and herein called AODV-MHR. Its performance was compared with that of AODV and OLSR by simulation. The simulation results showed that AODVMHR could achieve the advantages of both reactive and proactive routing approaches in performance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Effect of RTS/CTS Frames on the Performance of Ad Hoc-Based Mobile LAN

    Page(s): 63 - 68
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (799 KB) |  | HTML iconHTML  

    This paper analyzes the effect of RTS (Request To Send) and CTS (Clear To Send) frames on the network performance in the ad hoc-based mobile LAN. An ad hoc-based mobile LAN with two clients and one server is simulated using OPNET simulator to analyze network load, connection congestion window size and traffic received from each client in the FTP server. We found that both the connection congestion window size and network load about Clients are affected by the node mobility. The server terminates the FTP session with ClientA earlier if RTS/CTS is enabled. On the other hand, the server terminates the FTP session with ClientB later if RTS/CTS is enabled. We also identified that applying RTS/CTS scheme does not always improve the performance of the “traffic received from each client in the FTP server” in all network environments. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Application of Line Graph for Link Scheduling in Wireless Networks under M-hop Interference Model

    Page(s): 69 - 74
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (361 KB) |  | HTML iconHTML  

    In this paper, we study the link scheduling problem in wireless networks under M-hop interference model. In wireless networks, a scheduling algorithm is required to choose a subset of links at each time slot such that the packets do not corrupt due to interference. To deal with the interference in such a radio network different models have been introduced in the literature. In M-hop interference model two links are said to be conflicting links if they are within distance M of each other. It has been proven that for M > 1 the problems are generally NP-Hard. But for M=1, this problem becomes the classical matching problem, that can be solved in polynomial time and is a well studied subject. Having motivated to solve the above NP-hard problem, we utilize the concept of line graph from graph theory and incorporate it with the notion of conflict graph to simplify the development of link scheduling algorithms under M-hop interference model for a large class of graphs. We show that it is possible to achieve a low complexity discipline for link selection under M-hop interference model by applying a well known matching algorithm to the root graph of the conflict graph, provided that the conflict graph does not include claw, 6-Wheel and 4-Polyiamond as induced subgraphs. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Computer-Supported Collaborative Work and Its Application to E-Health

    Page(s): 75 - 80
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (427 KB) |  | HTML iconHTML  

    Most of the articles published in the last years present the asynchronous collaborative components integrated into the E-Health complex applications. They do not refer to the synchronous collaboration among the medical staff. A possible approach is because E-Health systems are patient-centered and the physicians, nurses and paramedics have to collaborate in a transparent manner not being focused on the synchronous collaborative tools. Our proposal is focused on advanced concepts for improving the telemedicine services and the real time collaboration among the medical staff. The article is based on a virtual collaboration prototype that supports both interpersonal and inter-process collaborative services and can be considered the core of a virtual healthcare community. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Algorithms for Extraction and Visualization of Metadata from Domain Name Server Records

    Page(s): 81 - 85
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (338 KB) |  | HTML iconHTML  

    Nowadays, security awareness is on every industry agenda. Mitigating threats and assessing risks is key to successful security posture and business continuity. Penetration tests are state-of-the-art and one of the main processes used by security professionals to discover, assess and evaluate a given infrastructure for potential security risks. On this paper we discuss Domain Name Server (DNS) information reconnaissance, a critical phase of any penetration test assessment, and present a tool that implements four different techniques to extract DNS metadata from a given domain namespace: TLD Rotation, Dictionary Attack, Brute Force Permutation and Typos. We present each algorithm and discuss the details of implementation of the tool. Finally, the integration of the tool with a powerful visualization engine to provide seamless graphical representations of the extracted data is discussed. The source code of the tool is available to further research. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Novel Approach for Scheduling in STDMA for High-Throughput Backbone Wireless Mesh Networks Operating within 60-80 GHz

    Page(s): 86 - 91
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (372 KB) |  | HTML iconHTML  

    This work proposes a novel approach to centralized scheduling in Spatial TDMA (STDMA) for a new class of high-throughput backbone broadband wireless mesh networks operating within 60-80 GHz. The approach is based on granted-to-requested ratio maxmin optimization criterion. During a research work, a centralized gradient algorithm for an optimal schedule construction was developed and its polynomial convergence was proven. The paper outlines key features of the high-throughput wireless mesh networks class under development, contains the scheduling problem formulation and introduces the polynomial algorithm for optimal resource allocation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Data Acquisition in Oceanographic Research Vessels

    Page(s): 92 - 97
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (659 KB) |  | HTML iconHTML  

    This paper describes the design and the development of a new real time data acquisition system which focuses on oceanographic research. The system has been implemented in several Spanish oceanographic platforms (vessels and land-sites) using very reliable MESH network that can still operate when one node breaks down or a connection goes bad. Service Oriented Architecture allows expandable access to real time and historical data. This system is applicable to any network of instrumentation where an integrated management of data and a wide range of access procedures are needed. We can frame these data acquisition system in a satellite communications environment both VSAT (C band) and TNX75 (X band). The target domain off these projects is to provide long-range data and optimize satellite communications resources. The challenging issue is to achieve cross-platform data-generating infrastructure, which in an optimized use of system resources and provide real time information to the user without depending on the location in which to generate or produce them. The project is focused mainly in relation to the acquisition of data, such as an integrated system of generation of data with a multilayer structure for accessing data consulting services, all using communications via satellite. To this day, we fully integrated platform and running, and we are expanding the services and optimizing the end-user interfaces with these new services. The eyelet of this document is to provide global technical community the current status in Spain, in regard to oceanographic data generation and exploitation of the same by the scientific community, from both the oceanographic vessels located anywhere of the world from locations ashore. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.