Wireless sensor network in precision agriculture: A survey

Internet of Things (IOT) is experiencing a super-fast growing phase. Wireless Sensor Networks (WSN), as the “five sense organs” and teleneuron of IOT, is developing fast along. Owing to the application-oriented characteristics of WSN, WSN applications may differ enormously in implementation methods. The WSN developers may have to rewrite the code for each and every application. Along with the increasing demand to WSN applications, WSN developers may have heavier tasks of programming for these applications. Thanks to TinyOS and NesC, an operating system and programming language designed especially for WSN, raises the WSN application's programming to a higher level. Large number of supported sensor hardware plus system provided and user-de-fined libraries eases WSN application programmers' jobs. How-ever, the massive amount of nodes' communication and networking, and security protection slows down the development pace. A unified and empirical WSN application implementation platform is one of the available solutions to the problem. This paper introduces an empirical WSN application implementation platform, which avails the WSN developers build an application with unified code template and network packet generation and processing strategies.

The current scenario of the world needs enhanced medical technology along with reduced expenses in order to fulfill the good health of patients that are suffering from chronic diseases. Because of the increase in the demand of healthcare infrastructure, it is getting complex to build and provide world-class facilities in order to maintain the health of everyone. In recent years, there has been a huge advancement of wireless networks and electronics which directed to the development of wireless sensor network (WSN). It is considered that WSNs have the ability to change the future. These networks comprise several sensors which are low-powered nodes that can sense the data nearby, perform limited computations and can radio communicate with other nodes. The parameters which can be sensed by sensors can be temperature, light or vibrations. Wireless sensor networks are under rapid research all over the globe, and researchers are working on it meticulously. This technology has the capability to replace thousands of wires in medical field which can increase reliability and portability. This paper will investigate the current applications of WSNs utilized globally in healthcare system, the limitations removed after the development of WSNs, what are scientists still working on in order to remove the barriers healthcare industry is facing currently, and what led to the development and utilization of WSNs in healthcare, current state of the art and need to integrate this technology in accordance with current medical scenario to enhance the healthcare system with limited medical expenses.

Wireless sensor networks (WSNs) are among the most promising technologies of the new millennium. The opportunities afforded by being able to program networks of small, lightweight, low-power, computation- and bandwidth-limited nodes have attracted a large community of researchers and developers. However, the unique set of capabilities offered by the technology produces an exciting but complex design space, which is often difficult to negotiate in an application context. Deploying sensing physical environments produces its own set of challenges, and can push systems into failure modes, thus revealing problems that can be difficult to discover or reproduce in simulation or the laboratory.Sustained efforts in the area of wireless networked sensing over the last 15 years have resulted in a large number of theoretical developments, substantial practical achievements, and a wealth of lessons for the future. It is clear that in order to bridge the gap between (on the one hand) visions of very large scale, autonomous, randomly deployed networks and (on the other) the actual performance of fielded systems, we need to view deployment as an essential component in the process of developing sensor networks: a process that includes hardware and software solutions that serve specific applications and end-user needs. Incorporating deployment into the design process reveals a new and different set of requirements and considerations, whose solutions require innovative thinking, multidisciplinary teams and strong involvement from end-user communities.This special feature uncovers and documents some of the hurdles encountered and solutions offered by experimental scientists when deploying and evaluating wireless sensor networks in situ, in a variety of well specified application scenarios.The papers specifically address issues of generic importance for WSN system designers: (i) data quality, (ii) communications availability and quality, (iii) alternative, low-energy sensing modalities and (iv) system solutions with high end-user added value and cost benefits. The common thread is deployment and deployment evaluation. In particular, satisfaction of application requirements, involvement of the end-user in the design and deployment process, satisfactory system performance and user acceptance are concerns addressed in many of the contributions. The contributions form a valuable set, which help to identify the priorities for research in this burgeoning area: Robust, reliable and efficient data collection in embedded wireless multi-hop networks are essential elements in creating a true deploy-and-forget user experience. Maintaining full connectivity within a WSN, in a real world environment populated by other WSNs, WiFi networks or Bluetooth devices that constitute sources of interference is a key element in any application, but more so for those that are safety-critical, such as disaster response. Awareness of the effects of wireless channel, physical position and line-of-sight on received signal strength in real-world, outdoor environments will shape the design of many outdoor applications. Thus, the quantification of such effects is valuable knowledge for designers. Sensors' failure detection, scalability and commercialization are common challenges in many long-term monitoring applications; transferable solutions are evidenced here in the context of pollutant detection and water quality. Innovative, alternative thinking is often needed to achieve the desired long-lived networks when power-hungry sensors are foreseen components; in some instances, the very problems of wireless technology, such as RF irregularity, can be transformed into advantages. The importance of an iterative design and evaluation methodology—from analysis to simulation to real-life deployment—should be well understood by all WSN developers. The value of this is highlighted in the context of a challenging WPAN video-surveillance application based on a novel Nomadic Access Mechanism. Cost benefits to be drawn from devising a WSN based solution to classic application areas such as surveillance are often a prime motivator for WSN designers; an example is offered here based on the use of intelligent agents for intrusion monitoring. Last but not least, the practicality and usability of the WSN solutions found for novel applications is key to their adoption. This is particularly true when the end-users of the developed technology are medical patients. The importance of feedback, elegant hardware encapsulation and extraction of meaning from data is presented in the context of novel orthopedic rehabilitation aids.Overall, this feature offers wide coverage of most issues encountered in the process of design, implementation and evaluation of deployable WSN systems. We trust that designers and developers of WSN systems will find much work of value, ranging from lessons learned, through solutions to known hurdles, to novel developments that enhance applications. Finally, we would like to thank all authors for their valuable contributions!

The Internet of Things (IoT) enables all objects to connect to the Internet and exchange data via different emerging technologies, which makes the intelligent identification and management a reality. Wireless sensor networks (WSNs), as a crucial basis of IoT, have been applied in many fields like smart health care and smart transportation. With the development of WSNs, data security has attracted more and more attention, and user authentication is a popular mechanism to ensure the information security of WSNs. Recently, many authentication mechanisms for wireless medical sensor networks (WMSNs) have been proposed, but most of the protocols cannot achieve the features of local password change and forward secrecy while resisting stolen smart card attack. To enhance the security based on previous work, an ECC-based secure three-factor authentication protocol with forward secrecy for WMSN is proposed in this paper. It utilizes a fuzzy commitment scheme to handle the biometric information. Meanwhile, fuzzy verifier and honey_list techniques are used to solve the contradiction of local password verification and mobile device lost attack. The security of our protocol is evaluated by provable security, Proverif tool, and information analysis. Besides, the comparisons with the relevant protocols are given, and the results indicate that our protocol is robust and secure for WMSN systems.

Wireless sensor networks are used in many fields. The needs to develop application based on wireless sensor networks are imperious. The node in wireless sensor networks nowadays is not only cheap but also reusable. To fulfill these requirements many technologies were researched and developed, one of which is Field Programmable Gate Array (FPGA). We can utilize the reconfigurable characteristic of FPGA to implement nodes of a wireless sensor network with little effort. This paper proposes the method to port TinyOS, an operating system particularly designed for wireless embedded sensor network, on FPGA system. This fills the gaps between FPGA and wireless sensor networks.

A wireless sensor network (WSN) is a collection of sensor nodes which can monitor the physical activities and attributes of a whole spectrum of objects and environments. The purpose of collecting this data and processing it in a meaningful manner requires that it adds significant value to the end user. WSN are deployed ever more frequently and applications vary from providing an early alert system on the activity of a volcano, to controlling the movements of livestock so that farming output can be maximized using virtual fencing. There are many challenges facing wireless sensor networks, with one being found in the uniqueness of each application, and challenges arise when WSN developers try to adequately test such applications when they are deployed with varying numbers of nodes, in all ranges of environmental conditions. To implement such systems in hardware involves a huge financial investment and from a development perspective prevents the developer from changing hardware platforms or communications protocols throughout the testing phase without incurring further financial hardship. Due to this fact, tools which can accurately simulate the behavior and performance of real world WSN applications are in high demand and a crucial aspect in the continued growth of WSN in the Internet of Things (IoT). This paper presents a cloud based system which makes various simulation platforms available to multiple users who wish to test WSN routing protocols or the hardware constraints of the various WSN platforms. This simulation testbed is hosted on a Dell PowerEdge R720 server in the communications laboratory in the University of Limerick and it is made available to users through the use of a virtual machine. This offers users access to many of the popular WSN simulation environments with vast computing resources and storage but at far reduced costs for protocol simulation.

Using wireless sensor networks (WSNs) in delay and reliability critical environments is highly desired due to their unique advantages such as low cost, ease of deployment, and redundancy. However, successful deployment of resource-limited WSNs in such applications requires strict quality-of-service (QoS) provisioning techniques to meet the desired latency and reliability targets of those applications. Implementation of QoS techniques in WSNs is significantly challenging since WSNs have been initially devised for low-data-rate non-real-time applications. Therefore, WSN designers and developers resort to different cross-layer interaction and optimization techniques to provision QoS in WSNs. In this paper, we present a survey on the state of the art of cross-layer QoS approaches in wireless terrestrial sensor networks to achieve delay and reliability bounds in critical applications. Our paper provides a unique classification of cross-layer QoS approaches in WSNs that allows surveying a large amount of studies with utmost clarity. Furthermore, we highlight the main challenges of implementing QoS protocols in WSNs and present an overview of QoS-aware WSN applications.

A novel model about the local-world linear expanding evolution of wireless sensor networks(WSNs) has been put forward in the basis of the classic BA scale-free model. The four types of internal evolving behaviors in wireless sensor networks are reflected in the dynamic process of the model. With the application of continuous field theory, the characteristics of network nodes' degree distribution are obtained, and it follows the power law distribution. This model not only has excellent robustness in avoiding the affection of random fault or failure of nodes, but also provides a new reference for constructing reliable topology of WSNs.

Wireless sensor networks (WSNs) is believed to be the first of the top ten technologies that will change the world in the future. With the development of WSNs in the military and commercial fields, the security of WSNs is becoming more and more important. The classical security mechanisms, namely authentication and encryption, can prevent some outsider attacks; however, these mechanisms are inefficient in detecting selective forwarding attacks on compromised nodes. Based on the observations above, in this paper, an improved greedy algorithm based on reputation evaluation mechanism is proposed to enforce cooperation among the nodes of WSNs and defend against the selective forwarding attacks. The performance of the improved greedy algorithm is verified by simulation, and the simulation result shows that the proposed algorithm can effectively resist the attacks of internal malicious nodes, it has better performance than the original greedy algorithm in terms of packet delivery ratio and drop ratio while there exist attack nodes.

Exclusive benefits gained by using the image and video sensors in Wireless Sensor Networks (WSNs), make the Wireless Video Sensor Networks (WVSNs), design and development of their structures, a trending topic. The main challenges of WSNs which are more critical in WVSNs are throughput and end-to-end delay. The radio transceivers recently used in WSN motes can work on different channels with very low switching time. Therefore, many multichannel protocols are proposed to improve the efficiency and throughput and decrease the packet drop rate of the network. Proposed algorithms rarely provide a particular solution to the end-to-end problem. Such delays are necessary parameters in real-time applications. In this paper a real-time multichannel protocol called RTMCH is suggested to address the end-to-end delay of a stream in WVSN. A flow-based channel assignment strategy is used for this purpose. Orthogonal channels are assigned to each flows based on many-to-one data-flow to minimize the contention and collision between different flows. Transmission power is a parameter that can be controlled to achieve desired link quality and to control link delay. Channel assignment problem aligns to a constrained optimization problem to make the specified end-to-end delay of each flow. A channel assignment and real-time packet forwarding scheme are then presented. Simulation results based on realistic channel and radio model shows that the RTMCH can efficiently use multiple channels and transmission power to meet specified end-to-end delay. The results also show better performance for RTMCH over a recent real-time protocol and basic multichannel schemes.

Wireless industrial sensor networks are wireless sensor networks which have been adapted to industrial applications. Most techniques for wireless sensor networks can be applied to wireless industrial sensor networks. However, for industrial applications of wireless industrial sensor networks, new requirements such as real-time, reliable delivery need to be considered. In this paper, we propose EARQ, which is a novel routing protocol for wireless industrial sensor networks. It provides real-time, reliable delivery of a packet, while considering energy awareness. In EARQ, a node estimates the energy cost, delay and reliability of a path to the sink node, based only on information from neighboring nodes. Then, it calculates the probability of selecting a path, using the estimates. When packet forwarding is required, it randomly selects the next node. A path with lower energy cost is likely to be selected, because the probability is inversely proportional to the energy cost to the sink node. To achieve real-time delivery, only paths that may deliver a packet in time are selected. To achieve reliability, it may send a redundant packet via an alternate path, but only if it is a source of a packet. Experimental results show that EARQ is suitable for industrial applications, due to its capability for energy efficient, real-time, reliable communications.

Background: In wireless sensor network (WSN), one of the best method is data aggregation for energy conservation. In numerous WSN applications, privacy preserving has become a very important issues with the development of WSNs. Purpose: Sensors are vulnerable for security threats due to the open deployment. Moreover, most of the routing algorithms does not consider security. Various methods like trust management, key management, firewalls, and intrusion detection for providing security were considered in the existing work. Between them, enhanced security is given by the trust management. Thus, in this paper, we used the secure trust-based enhanced LEACH routing (STELR) protocol to resolve security concerns. Methods: Here, cluster head is selected by using emperor penguin optimization (EPO) algorithm for data aggregation, and STELR is used to enable the security for routing. We can enable secure communication by checking the trustworthiness of a node. Results: The work is implemented in MATLAB platform, and the results are measured in terms of packet delivery ratio (PDR), throughput, end-to-end (E2E) delay, detection accuracy, energy dissipated, and trust probability (TP). Conclusions: Finally, the security concerns are resolved, which shows proposed approach that gives better performance when compared to existing techniques like LEACH and SDILR protocols.KeywordsWireless sensor networkEmperor penguin optimizationLEACH protocolTrust valueCluster headKey signature generationKey signature verification data aggregation and routing

Wireless sensor networks (WSNs) are indispensable building blocks for the Internet of Things (IoT). With the development of WSNs, privacy issues have drawn more attention. Existing work on the privacy-preserving range query mainly focuses on privacy preservation and integrity verification in two-tiered WSNs in the case of compromised master nodes, but neglects the damage of node collusion. In this paper, we propose a series of collusion-aware privacy-preserving range query protocols in two-tiered WSNs. To the best of our knowledge, this paper is the first to consider collusion attacks for a range query in tiered WSNs while fulfilling the preservation of privacy and integrity. To preserve the privacy of data and queries, we propose a novel encoding scheme to conceal sensitive information. To preserve the integrity of the results, we present a verification scheme using the correlation among data. In addition, two schemes are further presented to improve result accuracy and reduce communication cost. Finally, theoretical analysis and experimental results confirm the efficiency, accuracy and privacy of our proposals.

Wireless sensor and actuator networks (WSANs) are heterogeneous networks composed of many different nodes that can cooperatively sense the environment, determine an appropriate action to take, then change the environment’s state after acting on it. As a natural extension of wireless sensor networks (WSNs), WSANs inherit from them a variety of research challenges and bring forth many new ones. These challenges are related to dealing with imprecise and vague information, solving complicated optimization problems or collecting and processing data from multiple sources. Computational intelligence (CI) is an overarching term denoting a conglomerate of biologically and linguistically inspired techniques that provide robust solutions to NP-hard problems, reason in imprecise terms and yield high-quality yet computationally tractable approximate solutions to real-world problems. Many researchers have consequently turned to CI in hope of finding answers to a plethora of WSAN-related challenges. This paper reviews the application of several methodologies under the CI umbrella to the WSAN field. We describe and categorize existing works leaning on fuzzy systems , neural networks , evolutionary computation , swarm intelligence , learning systems , and their hybridizations to well-known or emerging WSAN problems along five major axes: 1) actuation; 2) communication; 3) sink mobility; 4) topology control; and 5) localization. The survey offers informative discussions to help reason through all the studies under consideration. Finally, we point to future research avenues by: 1) suggesting suitable CI techniques to specific problems; 2) borrowing concepts from WSNs that have yet to be applied to WSANs; or 3) describing the shortcomings of current methods in order to spark interest on the development of more refined models.

Moisture sensor acquires data of moisture content and water height of farmland; the data are transmitted by wireless sensor network and stored in data server to provide data mining and decision support for users, the utilization of wireless moisture sensor network could facilitate the excellent growth of crops and sustainable development of water resources. Based on self-design moisture sensor and actual monitoring needs of farmland moisture, this paper presents the architecture of wireless moisture sensor network and format of moisture data packet, designs the mechanisms of hierarchical storage, hierarchical error control and retransmission. Especially, the paper analyzes and simulates the mechanism of error control from respects of consuming time and correcting error ability, simulation results show that BCH coding is more suitable for wireless moisture sensor network than RS coding.