Event-driven Wireless Sensor Networks Research Articles

Security Issues and Challenges in Event-Driven Wireless Sensor Networks

Recently, wireless sensor networks (WSNs) have attracted a lot of attention from the network research community, especially in the aspect of event-driven wireless sensor networks (EWSNs), such as adversary locating, fire detection and so on.As the nature of importance of event monitoring, security has to be assured in both of communication and processing. However, due to the inherent resource constraints, security inEWSNs is faceddifferent issues and challenges than traditional WSNs.In this paper, we attempt to give an outline on the security issuesin the EWSNs. And then we propose a new secure architecture for it, which covers potential security issues. In this architecture, we analyze the possible threats and give out the correspondingcountermeasures.

Collaborative Event Driven Energy Efficient Protocol (CEDEEP)

This letter presents Collaborative Event Driven Energy Efficient Protocol (CEDEEP) that assures energy efficient operation of one-hop event driven Wireless Sensor Networks (WSN). CEDEEP takes advantage of spatiotemporal correlation of wireless sensor nodes' reporting in event driven WSN and uses collaborative communication to conserve more energy. The presented analytical results prove viability of this approach and show that CEDEEP offers considerable improvements in energy efficiency.

An event-driven WSN MAC protocol design based on active node and dynamic time slot allocation

The unique features of wireless sensor networks (WSNs) make them suitable for a wide range of applications in many different areas. However, with many of the protocols and algorithms used in traditional wireless networks, it is usually neither feasible nor possible to apply them directly to WSNs due to the strict resource constraints of tiny sensor nodes. Moreover, application-specific approaches for communication protocols are usually imposed since WSN applications have distinct requirements. In this study, event-driven WSN applications, where a number of sensor nodes are randomly and densely deployed in remote and difficult to reach locations, are targeted. In such applications, energy efficiency and latency are crucial design parameters since replacing or recharging the batteries of sensor nodes is extremely difficult, and any sensed data should be transmitted eventually. Considering this aspect, conventional time division multiple access-based medium access control (MAC) protocols are not well suited, although there are a few MAC protocols specifically designed for event-driven WSNs. In this paper, we introduce a MAC protocol, named modified bit-map--assisted (M-BMA), for event-driven WSN applications, designed by employing a new active node determination method (ANDM) and dynamic time slot allocation approach. Utilizing the proposed ANDM, we present that the M-BMA well supersedes its classical counterpart, offering up to approximately 49% better energy usage as well as up to about 68% fewer message delays.

A Dynamic Routing Algorithm for Data-Aggregation Optimization in Event-Driven Wireless Sensor Networks

A Dynamic Routing Algorithm for Data-Aggregation Optimization in Event-Driven Wireless Sensor Networks

A Survey on Event Detection and Transmission Protocols in an Event Driven Wireless Sensor Network

The most important goal of Event Driven Wireless Sensor Network (EDWSN) is to detect an event and pass this detected event to the users. Accurate event detection and fast event transmission play vital role in event detection. Many researchers have been proposed various techniques to detect events in an EDWSN. This paper describes a survey on event detection and event transmission protocols in an Event Driven Wireless Sensor Networks. We have classified these protocols into mainly two categories namely Sink Centric Event Detection and Transmission Protocols (SCEDTPs) and Node Centric Event Detection and Transmission Protocols (NCEDTPs). Then, these protocols are further classified into three categories under the constraints reliability, congestion resolution and energy efficiency. The advantages and disadvantages of each protocol also studied and we made the comparison of each protocol with different constraints.

Efficient Event Detecting Protocol in Event-Driven Wireless Sensor Networks

The most important goal in event-driven wireless sensor networks is to transmit the event information to users as soon as possible. One of the most important factors that would make it possible to reach this goal is the design of efficient detecting protocols. In this paper, we present an efficient event detecting protocol (EEDP) specified for event monitoring applications. In the event occuring area, each node broadcasts its primary detection result to make a decision corporately. And then the decision-made node will choose the next hop using the underlying routing protocol to forward a single alarm packet. To improve the reliable transmission of the single alarm packet, we use a dynamic multicopy scheme similar as conventional multipath routing for continuous flow. The simulation results validate that EEDP is a practical and efficient protocol for event detection applications where the constraints of end-to-end delay and reliability are stringent.

End-To-End Delay Optimization in Wireless Sensor Network (WSN)

In this paper, we are interested in optimizing the delay of event-driven wireless sensor networks, for which events does not occur frequently. In such systems, most of the energy is consumed when the radios are on, waiting for an arrival to occur. Sleep-wake scheduling is an effective mechanism to prolong the lifetime of this energy constrained wireless sensor networks by optimization of the delay in the network but this scheme could result in substantial delays because a transmitting node needs to wait for its next-hop relay node to wake up. An attempt has been made to reduce these delays by developing new method of packet forwarding schemes, where each nod opportunistically forwards a packet to the its neighboring node that wakes up among multiple candidate nodes. In this paper, the focus is to study how to optimize the packet forwarding schemes by optimization of the expected packet-delivery delays from the sensor nodes to the sink. Based on optimized delay scheme result, we then provide a solution to the central system about how to optimally control the system parameters of the sleep-wake scheduling protocol and the packet forwarding protocol to maximize the network lifetime, subject to a constraint on the expected end-to-end packet delivery delay. Our numerical results indicate that the proposed solution can outperform prior heuristic solutions in the literature, especially under the practical scenarios where there are obstructions, e.g., a lake or a mountain, in the area of wireless sensor networks.

Exploiting spatial correlation at the link layer for event-driven sensor networks

Wireless Sensor Networks (WSNs) can generally be classified into two categories: time-driven and event-driven. In an event-driven WSN, sensors report their readings only when they detect events. In such behaviour, sensors in the event area may suffer from higher contention. In this paper, we solve this problem by jointly considering two sub-issues. One is exploiting the spatial correlation of sensor data and the other is designing a specific MAC protocol. We propose a novel hybrid TDMA/CSMA protocol with the following interesting features that differentiate itself from traditional TDMA-based protocols: (1) the TDMA part is based on very loose time synchronisation and is triggered by the appearance of events; (2) the slot assignment strategy associated with the TDMA part takes the spatial correlation of sensor data into consideration and thus allows less strict slot allocation than conventional TDMA schemes. Simulation results show the efficiency of the proposed protocol.

Spatial Correlation-Based MAC Protocol for Event-Driven Wireless Sensor Networks

W ireless sensor networks is highly spatial correlated . Recently it has been proposed to select a subset of sensors nodes to transmit their data so as to prevent transmission of redundant data. In this paper, we investigate the ways of selecting sensor nod e s and develop a novel sp at ial correlation-based Medium Access Control ( MAC ) protocol for event-driven wireless sensor networks , referred as S C MAC. Based on a theoretical framework, S C MAC adopts priority node selection algorithm and collision avoidance mechanism so that transmission of redundant data is prevented when contending for the shared channel, while SCMAC prioritizes the transmission of route-thru packets. Simulation results show that our protocol achieves higher performance than CC-MAC in the aspect of energy consumption, transmission latency, packet delivery rate , packet drop rate and reconstruction distortion.

Modeling the Energy Performance of Event-Driven Wireless Sensor Network by Using Static Sink and Mobile Sink

Wireless Sensor Networks (WSNs) designed for mission-critical applications suffer from limited sensing capacities, particularly fast energy depletion. Regarding this, mobile sinks can be used to balance the energy consumption in WSNs, but the frequent location updates of the mobile sinks can lead to data collisions and rapid energy consumption for some specific sensors. This paper explores an optimal barrier coverage based sensor deployment for event driven WSNs where a dual-sink model was designed to evaluate the energy performance of not only static sensors, but Static Sink (SS) and Mobile Sinks (MSs) simultaneously, based on parameters such as sensor transmission range r and the velocity of the mobile sink v, etc. Moreover, a MS mobility model was developed to enable SS and MSs to effectively collaborate, while achieving spatiotemporal energy performance efficiency by using the knowledge of the cumulative density function (cdf), Poisson process and M/G/1 queue. The simulation results verified that the improved energy performance of the whole network was demonstrated clearly and our eDSA algorithm is more efficient than the static-sink model, reducing energy consumption approximately in half. Moreover, we demonstrate that our results are robust to realistic sensing models and also validate the correctness of our results through extensive simulations.

Minimizing Delay and Maximizing Lifetime for Wireless Sensor Networks With Anycast

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> In this paper, we are interested in minimizing the delay and maximizing the lifetime of event-driven wireless sensor networks for which events occur infrequently. In such systems, most of the energy is consumed when the radios are on, waiting for a packet to arrive. Sleep–wake scheduling is an effective mechanism to prolong the lifetime of these energy-constrained wireless sensor networks. However, sleep–wake scheduling could result in substantial delays because a transmitting node needs to wait for its next-hop relay node to wake up. An interesting line of work attempts to reduce these delays by developing “anycast”-based packet forwarding schemes, where each node opportunistically forwards a packet to the first neighboring node that wakes up among multiple candidate nodes. In this paper, we first study how to optimize the anycast forwarding schemes for minimizing the expected packet-delivery delays from the sensor nodes to the sink. Based on this result, we then provide a solution to the joint control problem of how to optimally control the system parameters of the sleep–wake scheduling protocol and the anycast packet-forwarding protocol to maximize the network lifetime, subject to a constraint on the expected end-to-end packet-delivery delay. Our numerical results indicate that the proposed solution can outperform prior heuristic solutions in the literature, especially under practical scenarios where there are obstructions, e.g., a lake or a mountain, in the coverage area of the wireless sensor network. </para>

Datacollection in Event-Driven Wireless Sensor Networks with Mobile Sinks

We present a two-tier distributed hash table-based scheme for data-collection in event-driven wireless sensor networks. The proposed method leverages mobile sinks to significantly extend the lifetime of the sensor network. We propose localized algorithms using a distributed geographic hash-table mechanism that adds load balancing capabilities to the data-collection process. We address the hotspot problem by rehashing the locations of the mobile sinks periodically. The proposed mobility model moves the sink node only upon the occurrence of an event according to the evolution of current events, so as to minimize the energy consumption incurred by the multihop transmission of the event-data. Data is collected via single-hop routing between the sensor node and the mobile sink. Simulation results demonstrate significant gains in energy savings, while keeping the latency and the communication overhead at low levels for a variety of parameter values.

State monitoring information routing protocol for event-driven WSN

To balance the energy consumption of nodes in Wireless Sensor Network (WSN),the authors proposed a routing protocol to transmit the network health state information based on clustering routing algorithm,named Event-Driven State Monitoring Information Routing (ED-SMIR). ED-SMIR adopted the way with single-hop turning to multi-hop in rotation according to energy consumption rate. For the route from cluster head to the sink,ED-SMIR took multi-hop routing. The simulation results show that,compared with LEACH and EDBCM,ED-SMIR has less energy consumption,and it can balance the energy of the entire network and extend the survival time of network effectively.

An Energy-Efficient Routing Protocol for Event-Driven Dense Wireless Sensor Networks

The routing energy efficiency of a wireless sensor network is a crucial issue for the network lifetime. In this article, we propose MICRO (MInimum Cost Routing with Optimized data fusion), an energy-efficient routing protocol for event-driven dense wireless sensor networks. The proposed routing protocol is an improvement over the formerly proposed LEACH and PEGASIS protocol, which is designed to be implemented mainly with node computations rather than mainly with node communications. Moreover, in the routing computation the proposed scheme exploits a new cost function for energy balancing among sensor nodes, and uses an iterative scheme with optimized data fusions to compute the minimum-cost route for each event-detecting sensor node. Compared to the PEGASIS routing protocol, MICRO substantially improves the energy-efficiency of each route, by optimizing the trade-off between minimization of the total energy consumption of each route and the balancing of the energy state of each sensor node. It is demonstrated that the proposed protocol is able to outperform the LEACH and the PEGASIS protocols with respect to network lifetime by 100–300% and 10–100%, respectively.

Average Channel Utilization of CSMA With Geometric Distribution Under Varying Workload

Performance analysis of fixed-size contention window carrier sense multiple-access (CSMA) protocol with geometric distribution for slot selection probability is addressed in the paper. This MAC scheme, called Sift, was initially proposed for large-scale event-driven wireless sensor networks. The goal of the present paper is to evaluate the standard performance measures (throughput, protocol capacity, collision rate, and mean access delay) for geometrically distributed CSMA both in the context of data-centric dense sensor networks and node-centric industrial automation systems. The analytical approach based on the stochastic analysis has been applied. To demonstrate how the protocol is able to cope with bursty traffic, the average throughput defined over a specified workload range has been introduced and examined. Using the average throughput as the performance criterion, the geometric CSMA has been compared to conventional CSMA schemes with uniform distribution. The latter are represented by the classical p-persistent CSMA and the predictive p-persistent CSMA used in LonWorks control networks. It is shown that G-CSMA is overload-tolerant event-driven MAC protocol since the average throughput may be kept on high level in wide range of workload if the shape of geometric distribution is well chosen.

Energy and delay optimized contention for wireless sensor networks

In wireless sensor network (WSN) studies, the main objective is minimizing the energy consumption so that the lifetime is maximized under the limited battery capacity constraints. Additionally, in most event-driven WSN applications, the end-to-end delay, and hence, the medium access delay should be minimized. Majority of the WSN MAC protocols are contention-based wherein contention window size setting involves an important trade-off between the collision probability and idle listening durations in contentions where both are aimed to be lowered for efficient network operation. In this paper, the energy optimizing and the delay optimizing contention window sizes are derived as a function of the number of contending nodes. For this purpose, we present separate analyses for the contention delay and for the energy consumed which are verified with detailed simulations. In order to obtain close to optimal performance values in a distributed manner, we propose a method for estimating the number of contending nodes since the individual wireless sensor nodes do not have this information readily. Simulations of an event-driven WSN application verify that the proposed method successfully improve both delay and energy efficiency of the contention-based medium access. The end-to-end network performance is also investigated by employing a geographical routing protocol. Results show that using the heuristic method proposed that use the optimum contention window size analyses presented, the overall network performance can be improved without incurring any overhead to the system.

An Inter-cluster Communication based Energy Aware and Fault Tolerant Protocol for Wireless Sensor Networks

The ambient intelligence paradigm is built upon Ubiquitous Computing (UC), in which the computing devices are embedded in the environment with the purpose of enhancing the human experience at home, workplace/ office, learning, health care etc. The UC applications aim at providing services to the users anywhere, anytime in an unobtrusive, seemingly invisible way. Wireless sensor networks (WSNs) have great potential for UC applications and are envisioned to revolutionize them. This paper presents a clustering routing protocol for event-driven, query-based and periodic WSNs. The protocol aims at optimizing energy dissipation in the network as well as providing network's fault tolerance and connectivity. Message propagation is accomplished by using short distance transmissions by employing nearest neighbor nodes between neighboring clusters. Moreover, the algorithm proposes using an energy efficient approach by alternating the nodes responsible for inter-cluster communication inside one cluster. The algorithm also aims at even energy dissipation among the nodes in the network by alternating the possible routes to the Sink. This helps to balance the load on sensor nodes and increases the network lifetime, while avoiding congested links at the same time. We discuss the implementation of our protocol, present its proof of correctness as well as the performance evaluation through an extensive set of simulation experiments.

A Localized Route Discovery for On-Demand Routing Protocols in Event-Driven Wireless Sensor Networks

In this paper, the problem of Redundant Duplicated RREQ Network-wide Flooding (RDRNF), induced by multiple sensor nodes during route discovery in event-driven wireless sensor networks, is described. In order to reduce the number of signaling messages during the route discovery phase, a novel extension, named the Localized Route Discovery Extension (LRDE), to the on-demand ad hoc routing protocol, is proposed. The LRDE reduces energy consumption during route discovery. The heuristically and temporarily selected Path Set-up Coordinator (PSC) plays the role of a route request broker that alleviates redundant route request flooding. The LRDE also sets a route path be aggregation-compatible. The PSC can effectively perform data aggregation through the routing path constructed by the LRDE. The simulation results reveal that significant energy is conserved by reducing signaling overhead and performing data aggregation when LRDE is applied to on-demand routing protocols.