44,417 research outputs found

    Local Multicoloring Algorithms: Computing a Nearly-Optimal TDMA Schedule in Constant Time

    Get PDF
    The described multicoloring problem has direct applications in the context of wireless ad hoc and sensor networks. In order to coordinate the access to the shared wireless medium, the nodes of such a network need to employ some medium access control (MAC) protocol. Typical MAC protocols control the access to the shared channel by time (TDMA), frequency (FDMA), or code division multiple access (CDMA) schemes. Many channel access schemes assign a fixed set of time slots, frequencies, or (orthogonal) codes to the nodes of a network such that nodes that interfere with each other receive disjoint sets of time slots, frequencies, or code sets. Finding a valid assignment of time slots, frequencies, or codes hence directly corresponds to computing a multicoloring of a graph GG. The scarcity of bandwidth, energy, and computing resources in ad hoc and sensor networks, as well as the often highly dynamic nature of these networks require that the multicoloring can be computed based on as little and as local information as possible

    Channel Sharing based Medium Access Control Protocol for Wireless Nano Sensing Network

    Get PDF
    Recent advancement and grown up technologies has enabled the development and implementation of low-cost, energy efficient and versatile sensor networks. Sensor networks are built up with sensors that have the ability to sense physical or environmental property. Assumption can be made that Wireless Sensing Network (WSN) is able to sense environmental conditions at Nano and gaseous level. This architecture of Wireless Sensor Network is maintained by a sub-layer named Medium Access Control Layer that provides addressing and channel access control mechanism among multiple nodes of the network and makes these nodes capable to communicate with other nodes through a shared medium. The hardware that implements the MAC is referred to as a medium access controller. This paper finds the problems in selection of cluster nodes and transmitting data and also proposes an improved MAC protocol to minimize the problem

    Energy-efficient communication protocol in linear wireless sensor networks

    Get PDF
    Wireless sensor networks (WSNs) have been widely recognized as a promising technology that can enhance various aspects of structure monitoring and border surveillance. Typical applications, such as sensors embedded in the outer surface of a pipeline or mounted along the supporting structure of a bridge, feature a linear sensor arrangement. Economical power use of sensor nodes is essential for long-lasting operation. In this paper, we present wireless High-Level Data Link Control (HDLC) a novel approach to energy-efficient data routing to a single control center in a linear sensor topology. Applying a standard data layer along with a time division multiple access (TDMA)-based Medium Access Control (MAC) and time synchronization technique specifically designed for the linear topology, we address the interoperability problem with guaranteed energy efficiency and data link performance in linear sensor topology.Peer Reviewe

    An Adaptable Energy-Efficient Medium Access Control Protocol for Wireless Sensor Networks

    Get PDF
    Wireless networks have become ubiquitous recently and therefore their usefulness has also become more extensive. Wireless sensor networks (WSN) detect environmental information with sensors in remote settings. One problem facing WSNs is the inability to resupply power to these energy-constrained devices due to their remoteness. Therefore to extend a WSN\u27s effectiveness, the lifetime of the network must be increased by making them as energy efficient as possible. An energy efficient medium access control (MAC) can boost a WSN\u27s lifetime. This research creates a MAC protocol called Adaptive sensor Medium Access Control (AMAC) which is based on Sensor Medium Access Control (SMAC) which saves energy by periodically sleeping and not receiving. AMAC adapts to traffic conditions by incorporating multiple duty cycles. Under a high traffic load, AMAC has a short duty cycle and wakes up often. Under a low traffic load, AMAC has a longer duty cycle and wakes up infrequently. The AMAC protocol is simulated in OPNET Modeler using various topologies. AMAC uses 15% less power and 22% less energy per byte than SMAC but doubles the latency. AMAC is promising and further research can decrease its latency and increase its energy efficiency

    Comparison of CSMA based MAC protocols of wireless sensor networks

    Full text link
    Energy conservation has been an important area of interest in Wireless Sensor networks (WSNs). Medium Access Control (MAC) protocols play an important role in energy conservation. In this paper, we describe CSMA based MAC protocols for WSN and analyze the simulation results of these protocols. We implemented S-MAC, T-MAC, B-MAC, B-MAC+, X-MAC, DMAC and Wise-MAC in TOSSIM, a simulator which unlike other simulators simulates the same code running on real hardware. Previous surveys mainly focused on the classification of MAC protocols according to the techniques being used or problem dealt with and presented a theoretical evaluation of protocols. This paper presents the comparative study of CSMA based protocols for WSNs, showing which MAC protocol is suitable in a particular environment and supports the arguments with the simulation results. The comparative study can be used to find the best suited MAC protocol for wireless sensor networks in different environments.Comment: International Journal of AdHoc Network Systems, Volume 2, Number 2, April 201

    Fast Desynchronization For Decentralized Multichannel Medium Access Control

    Get PDF
    Distributed desynchronization algorithms are key to wireless sensor networks as they allow for medium access control in a decentralized manner. In this paper, we view desynchronization primitives as iterative methods that solve optimization problems. In particular, by formalizing a well established desynchronization algorithm as a gradient descent method, we establish novel upper bounds on the number of iterations required to reach convergence. Moreover, by using Nesterov's accelerated gradient method, we propose a novel desynchronization primitive that provides for faster convergence to the steady state. Importantly, we propose a novel algorithm that leads to decentralized time-synchronous multichannel TDMA coordination by formulating this task as an optimization problem. Our simulations and experiments on a densely-connected IEEE 802.15.4-based wireless sensor network demonstrate that our scheme provides for faster convergence to the steady state, robustness to hidden nodes, higher network throughput and comparable power dissipation with respect to the recently standardized IEEE 802.15.4e-2012 time-synchronized channel hopping (TSCH) scheme.Comment: to appear in IEEE Transactions on Communication

    Performance Evaluation with Energy Consumption, Cluster Throughput and Packet Delivery Ratio of S-MAC Protocol in Wireless Sensor Network

    Get PDF
    Wireless sensor network are battery operated, and hence increasing the network lifetime is one of the primary concerns. This paper introduces energy efficient Sensor-Medium Access Control (S-MAC) protocol used in sensor network. Energy consumption is the main problem in wireless sensor network. So decrease the energy consumption and increase the network lifetime of sensor nodes in sensor networks using by S-MAC protocol. S-MAC protocol uses techniques for reduce energy consumption and also support self-configuration. The first, neighboring nodes are synchronized and go to sleep periodically. Second, the synchronized neighboring nodes make a virtual cluster to synchronize their listen and sleep periods, so the control packet overhead is kept low. Third, message passing is used to decrease latency and control overhead. In present work cluster is formed then cluster head is selected, and cluster head is fixed. S-MAC protocol was simulated in NS-2. To study the performance of S-MAC in terms of network lifetime, cluster throughput, packet delivery ration, total power and energy consumption for cluster head

    MULTI-CHANNEL MAC PROTOCOL FOR ENERGY SAVING IN WIRELESS SENSOR NETWORKS

    Get PDF
    Wireless Sensor Network (WSN) is a self-organizing and distributed collection of small sensor nodes with limited energy are connected wirelessly to the sink, where the information is needed. The significant trait for any Wireless Sensor Network is power consumption since WSNs finds its most of the applications in unsafe, risky areas like Volcano eruption identification, Warfield monitoring, where human intervention is less or not possible at all. Hence designing a protocol with minimum energy consumption as a concern is an important challenge in increasing the lifetime of the sensor networks. Medium Access Control (MAC) Layer of WSN consumes much of the energy as it contains the radio component. Energy problems in MAC layer include collision, idle listening, and protocol overhead. Our Proposed MAC protocol provides solution for the problem of: collision by providing multiple channels; idle listening by providing sleeping mechanism for the nodes other than the active node; overhead by reducing the number of control messages. Avoiding collision results in the decrease in number of retransmissions which consumes more energy, avoiding idle listening problem will fairly increase the lifetime of the sensor node as well as the network’s lifetime and reducing overhead in turn consumes less energy
    • …
    corecore