Enabled Wireless Sensor Networks Research Articles

An Efficient Mobility Model for Improving Transmissions in Multi-UAVs Enabled WSNs

Multi-Unmanned Aerial Vehicle (UAV) enabled Wireless Sensor Networks (WSNs) provide a wide range of applications, covering civilian and military expeditions along with geographical navigation, control, and reconnaissance. The coordinated networks formed between the UAVs and the WSNs help in enhancing the issues related to quality as well as coverage. The overall coverage issues result in starvation as an effect of long waiting time for the nodes, while forwarding the traffic. The coverage problem can be resolved by an intelligent choice of UAV way-points. Therefore, a specialized UAV mobility model is required which takes into account the topological structure as well as the importance of strategic locations to fix UAV way-points and decide the data transmission paradigm. To resolve this problem, a novel mobility model is proposed, which takes into account the attraction factor for setting up the way-points for UAV movements. The model is capable of deciding between the locations which result in more coverage, increased throughput with lesser number of UAVs employed, as justified by the simulation results and comparative evaluations.

Trust Based Scheme for IoT Enabled Wireless Sensor Networks

Many research in the literature address the problem of aggregating data in wireless sensor network (WSN) applications. Data aggregation techniques of WSN using external mobile elements (ME) are, recently, proposed. Only few of the proposed techniques consider the trust factor when selecting one network component to send the data to the base station. In this paper, we introduce a new trust scheme that assigns the task of sending the aggregated data to only the most reliable external MEs of the WSN, in order to reduce data loss. Experimental results show that the proposed scheme performs well in terms of reducing the data and energy loss while not negatively affecting the network coverage.

Energy Efficient Consecutive Packet Transmissions in Receiver-Initiated Wake-Up Radio Enabled WSNs

In wake-up radio (WuR)-enabled wireless sensor networks, data communication among nodes is triggered in an on-demand manner, by either a sender or a receiver. For receiver-initiated WuR (RI-WuR), a receiving node wakes up sending nodes through a wake-up call. Correspondingly sending nodes transmit packets in a traditional way by competing with one another multiple times in a single operational cycle. In this paper, we propose a receiver-initiated consecutive packet transmission WuR (RI-CPT-WuR) medium access control (MAC) protocol, which eliminates multiple competitions to achieve higher energy efficiency. Furthermore, we develop two associated discrete time Markov chains (DTMCs) for evaluating the performance of RI-CPT-WuR and an existing RI-WuR MAC protocol. Using the solutions from the DTMC models, closed-form expressions for network throughput, average delay, packet reliability ratio, energy consumption and lifetime, and energy efficiency for both protocols are obtained. Numerical results demonstrate the superiority of the RI-CPT-WuR protocol.

A Cooperative Clustering Protocol With Duty Cycling for Energy Harvesting Enabled Wireless Sensor Networks

This paper proposes a cooperative clustering protocol based on the low energy adaptive clustering hierarchy approach to enhance the longevity of energy harvesting-based wireless sensor networks (EH-WSN). In the proposed protocol, to ensure that any energy consumption associated with the role of the cluster head (CH) is shared between the nodes, the CH role is alternated between the nodes using duty cycling as a function of their individual energy harvesting capabilities. Furthermore, to maintain an energy neutral operation when not acting as a CH, the nodes adopt a data transmission duty cycle and any excess energy is invested in relaying other nodes’ packets. To optimize the relaying performance, a novel cross-layer cooperative TDMA scheme is also presented. The optimal number of clusters in an EH-WSN is analyzed in terms of energy consumption, latency, and bandwidth utilization. Simulations, performed using GreenCastalia, demonstrate tangible performance enhancements in adopting the proposed protocol over benchmark schemes in terms of throughput and lifetime, particularly under highly constrained energy conditions.

Lifetime Maximization via Hole Alleviation in IoT Enabling Heterogeneous Wireless Sensor Networks.

In Internet of Things (IoT) enabled Wireless Sensor Networks (WSNs), there are two major factors which degrade the performance of the network. One is the void hole which occurs in a particular region due to unavailability of forwarder nodes. The other is the presence of energy hole which occurs due to imbalanced data traffic load on intermediate nodes. Therefore, an optimum transmission strategy is required to maximize the network lifespan via hole alleviation. In this regard, we propose a heterogeneous network solution that is capable to balance energy dissipation among network nodes. In addition, the divide and conquer approach is exploited to evenly distribute number of transmissions over various network areas. An efficient forwarder node selection is performed to alleviate coverage and energy holes. Linear optimization is performed to validate the effectiveness of our proposed work in term of energy minimization. Furthermore, simulations are conducted to show that our claims are well grounded. Results show the superiority of our work as compared to the baseline scheme in terms of energy consumption and network lifetime.

Cognitive Radio Enabled Wireless Sensor Networks and Survivability Challenges

Cognitive Radio Enabled Wireless Sensor Networks and Survivability Challenges

A Survey of Multimedia Streaming in Wireless Sensor Networks: Progress, Issues and Design Challenges

Advancements in Complementary Metal Oxide Semiconductor (CMOS) technology have enabled Wireless Sensor Networks (WSN) to gather, process and transport multimedia (MM) data as well and not just limited to handling ordinary scalar data anymore. This new generation of WSN type is called Wireless Multimedia Sensor Networks (WMSNs). Better and yet relatively cheaper sensors that are able to sense both scalar data and multimedia data with more advanced functionalities such as being able to handle rather intense computations easily have sprung up. In this paper, the applications, architectures, challenges and issues faced in the design of WMSNs are explored. Security and privacy issues, over all requirements, proposed and implemented solutions so far, some of the successful achievements and other related works in the field are also highlighted. Open research areas are pointed out and a few solution suggestions to the still persistent problems are made, which, to the best of my knowledge, so far have not been explored yet.

Network throughput analysis of IEEE 802.15.4 enabled wireless sensor networks with FEC coding under external interference

IEEE 802.15.4 enabled wireless sensor networks are often impacted by the coexistence of different sources of external interference sharing the ISM band. Such external interference may significantly deteriorate achievable wireless sensor network throughputs due to uncontrollable collisions of interference transmissions with IEEE 802.15.4 packets. Forward error correction may be considered as a mechanism to alleviate the resiliency of IEEE 802.15.4 packets against partial collisions due to interference. In this paper, theoretical analysis of network throughput of IEEE 802.15.4 enabled wireless sensor networks under external interference with deployment of FEC will be presented. The throughput performance of IEEE 802.15.4 network under FEC deployment is governed by the percentage of collided bits within IEEE 802.15.4 coded payloads that the FEC code can withstand. The analysis in this paper considers convolutional codes as FEC candidate codes for IEEE 802.15.4 networks and proceeds to theoretically derive collision percentage thresholds that convolutional codes may tolerate under Viterbi decoding. Numerical results indicate that an optimal FEC coding rate exists for a given IEEE 802.15.4 and external interference configuration. The optimal coding rate introduces enough resiliency for the IEEE 802.15.4 transmissions to withstand external interference. Any additional redundancy bits for more robust codes would render unneeded protection that unnecessarily reduces the goodput of IEEE 802.15.4 networks.

An Efficient and Novel Key Establishment Scheme for Internet Enabled Wireless Sensor Network in the Context of IOT

Wireless sensor networks (WSN) behave as a digital skin, providing a virtual layer where the information about the physical world can be accessed by any computational system. As a result, they are an invaluable resource for realizing the vision of the Internet of Things (IoT). Many applications of sensor networks require secure communication. Thus establishing a secure channel between any two sensor-nodes in WSNs/IESNs is important for many applications, such as secure data exchange, secure data aggregation, and secure routing. In this paper, first we show why existing three party key establishment schemes cannot be easily applied to IESN. Second we propose an extension of traditional three-party key establishment schemes (such as SNEP, BBF and OR). The method provides DoS and Sybil attack resistance and benefits from low communication cost, independence of prior sensor deployment knowledge and support for node mobility. In comparison to the previous well-known three-party schemes, our extension not only fixes DoS vulnerability, but also provides some other advantages such as significant efficiency. The proposed key establishment scheme can be used not only for establishing shared key between any two sensors, but it is applicable for establishing shared secret between any two entities/ things in the context of IoT.

Topology Control for Harvesting Enabled Wireless Sensor Networks: A Design Approach

While there has been a lot of research on energy efficient topology control protocols destined for different applications, topology control has never been explored in the presence of harvesting enabled sensors. Largely, researchers in this domain have considered a fixed battery design. We argue that arrival of harvesting enabled sensors necessitates rethink of topology control. The objective of topology control in this context should not be to minimize the spent energy and maintain a reduced topology, but to maximize fault tolerance in the network and increase the sensing coverage region. In this work, we first describe a taxonomy of existing topology control schemes and analyze the impact of reduced topology over fault tolerance and sensing coverage. We then describe the necessity of new design parameters in the presence of harvest-able ambient energy. We also outline guiding principles for designing a harvesting enabled topology control scheme. To cater for whether such a scheme is feasible or not, an insight is also provided onto the solar energy availability from solar radiations for near perpetual operation--as an example of available ambient energy. Based on the insight gained from the solar radiations availability, we explain why new design parameters are required for performance measurement of harvesting enabled sensors. The mathematical and empirical findings reveal that the topology control strategies, which do not take into account harvesting opportunity, are unable to provide better results in terms of fault tolerance and sensing coverage.

Optimized Battery Models Observations for Static, Distance Vector and On-Demand Based Routing Protocols Over 802.11 Enabled Wireless Sensor Networks

We analyze a wireless sensor network system to address the impact of different battery models on five routing protocols. We present an analytical model to understand the key performance metrics like average jitter, first and last packet received, total bytes received, average end to end delay, throughput and energy consumption. We have proposed the various parameters of our model for static, distance vector and on demand based routing protocols along with linear and service life estimator battery model. The validation of proposed parameters through simulation and derive substantial investigations in wireless sensor network system.

Progress Towards the First Wireless Sensor Networks Consisting of Inkjet-Printed, Paper-Based RFID-Enabled Sensor Tags

This paper discusses the evolution towards the first integrated radio-frequency identification (RFID)-enabled wireless sensor network infrastructure using ultra-high frequency/radio frequency (UHF/RF) RFID-enabled sensor nodes and inkjet-printed electronics technologies on flexible and paper substrates for the first time ever. The first sections highlight the unique capabilities of inkjet printed electronics as well as the benefits of using paper as the ultra-low-cost, conformal and environmentally friendly substrate for the mass-scale ubiquitous implementation of the first RFID-enabled wireless sensing applications. Various inkjet-printed antenna configurations are presented for enhanced-range compact RFID-enabled sensing platforms in “rugged” environments up to 7 GHz, followed by the discussion of their 2-D integration with integrated circuit (IC) and sensors on paper. This integration is extended to a power-scavenging “smart-shoe” batteryless integrated RFID module on paper that could be used for autonomous wearable sensing applications with enhanced range. The paper concludes discussing the details for establishing for the first time an asynchronous wireless link between the aforementioned RFID-tags and a widely used commercial wireless sensor network (WSN) mote using a simplified protocol; a paramount step that could potentially create ubiquitous ultra-low-cost sensor networks and large-scale RFID implementations eliminating the need of expensive RFID reader infrastructure and linking RFIDs to the mature level of WSNs.

Level the buffer wall: Fair channel assignment in wireless sensor networks

In this paper, we study the trade-off between network throughput and fairness in a multi-channel enabled wireless sensor network (WSN). Traditional approaches attempt to solve the two problems in an isolated manner without a joint design. Although there are schemes aiming to improve either throughput or fairness, respectively, our empirical studies show that solutions to these two problems cannot be simply combined to achieve better throughput and fairness simultaneously. Away from the traditional belief, the number of channels in WSNs with Telosb sensor nodes operating at 2.4 GHz band can be up to 83 and the orthogonal channels can be up to 27. The switching overhead in terms of time and energy cost is relatively small. The averaged switching time for a sender is about 0.34 ms and the additional energy consumption caused by channel switching is no more than 2% when 10 4 packets with 43 bytes of each are sending out continuously. Furthermore, we observe a buffer wall phenomenon which is one of the main reasons causing network throughput degradation and unfairness. To strike a better trade-off between the network throughput and fairness, we design a novel multi-channel assignment algorithm, targeting at maximizing the minimal data sending rate. The key idea of the proposed algorithm is to level down the buffer wall so that the buffer usage of nodes can be evenly distributed. As such, the bandwidth of bottleneck nodes can be fully utilized and the unfairness due to the node locality can be removed. We prove that the achieved data sending rate is no less than 4/9 of the optimal rate in theory. Our experimental results based on both chain and uniformly random sensor deployment topologies show that the minimal data sending rate can be improved by up to 100% comparing with the existing work TMCP.

On the implementation and evaluation of an elliptic curve based cryptosystem for Java enabled Wireless Sensor Networks

This paper considers the impact of the provision of security for a Java enabled wireless sensor networking platform. In 2007, Sun Microsystems, Inc. released a Java programmable platform; namely Sun Small Programmable Object Technology (Sun SPOT). Given the more intuitive application development environment, it is envisaged that real applications will emerge at a more rapid pace, and as such the importance of the provision of security remains to the fore. The only provision of security, to-date, is that of an industry standard TLS (Transport Layer Security) implementation at the Application Layer; rooted from an ECC (Elliptic Curve Cryptography) based public-key cryptosystem. This work demonstrates that the employment of TLS results in a reduction of 70% of network lifetime; a significant cost to provide security. Given this cost, alternative methods of securing a Sun SPOT based sensor network are considered, culminating in the specification of a cross-layer, hybrid security architecture.

Web Enabled Wireless Sensor Networks for Facilities Management

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The cornerstone of building and overall facilities management is accurate and up-to-date monitoring of the context of the enterprise building environment and its surroundings, usually performed by sensors dispersed throughout the premises. Currently, the majority of building management systems is tightly coupled with the sensors that they utilize, restricting their extensibility. The emergence of Wireless Sensor Networks (WSNs) has brought significant benefits as far as monitoring is concerned, since they are more cost-efficient, due to the lack of wiring installations, compared to wired sensor solutions and allow for flexible positioning of the sensors, especially when building retrofitting is concerned. In line with the established move towards integration of enterprise level services, it is beneficial to consider the WSNs within that scope. In this paper, we propose to exploit a service oriented architecture for developing an enterprise networking environment that is used for integrating facilities management applications and building management systems with other operational enterprise functions for the purpose of information sharing and monitoring, controlling, and managing the enterprise environment. The WSN is viewed as an information service provider not only to building management systems but also to wider applications in the enterprise infrastructure. We provide specification and implementation details of the proposed architecture and discuss evaluation planning. </para>

MWSN for Large Scale Mobile Sensing

This paper reviews the state-of-the-art features introduced by sink mobility into wireless sensor networks (WSN), and introduces the architecture of mobile enabled Wireless Sensor Network (mWSN) to realize large-scale information gathering via networked wireless sensors and mobile sinks. After introducing the mobile sensing scenarios, some fundamental design parameters in mWSN have been investigated, such as cluster size, sink velocity, transmission range, and packet length. Our contributions include: (1) A cluster formation method has been proposed via multihop forwarding to form a cluster around the expected position of a mobile sink, in order to guarantee packet delay and minimize energy consumption. (2) Analysis of the performance influence by sink mobility leads to the conclusion that the optimal sink velocity must make a compromise between sink-sensor meeting delay and message delivery delay. (3) Finding that large transmission range and short packet length are both of benefit to lower the outage probability of packet transmission. Extensive simulations have been designed to evaluate the performance of mWSN in terms of packet delay, energy consumption and outage probability of packet transmission.