Probabilistic routing protocol for a hybrid wireless underground sensor networks

A wireless underground sensor network (WUSN) is defined as a network of wireless sensor devices in which all sensor devices are deployed completely underground (network sinks or any devices specifically for relay between sensors and a sink may be aboveground). In hybrid wireless underground sensor network (HWUSN), communication between nodes is implemented from underground‐to‐air or air‐to‐underground, not underground‐to‐underground. This paper proposes a novel hybrid underground probabilistic routing protocol that provides an efficient means of communication for sensor nodes in HWUSN. In addition, signal propagation based on the shadowing model for underground medium is developed. The proposed routing protocol ensures high packet throughput, prolongs the lifetime of HWUSN and the random selection of the next hop with multi‐path forwarding contributes to built‐in security. Moreover, the proposed mechanism utilizes an optimal forwarding (OF) decision that takes into account of the link quality, and the remaining power of next hop sensor nodes. The performance of proposed routing protocol has been successfully studied and verified through the simulation and real test bed. Copyright © 2011 John Wiley & Sons, Ltd.     

Efficient delivery‐guaranteed geographic routing in 3D wireless sensor networks with holes

In many applications, sensor nodes are deployed in a 3D environment with obstacles, in which case a great deal of holes exist in 3D wireless sensor networks constructed. Recently, several geographic routing protocols are proposed for 3D wireless sensor networks. Each of them, however, cannot guarantee packet delivery or demands a long routing path to turn around a hole. In this paper, we first introduce a method of constructing a guide to the navigation on the surface of a hole. Subsequently, a geographic routing protocol termed the Greedy‐Guide_Navigation‐Greedy protocol (GGNG) that can always route a packet to turn around a hole with the help of the guide is proposed. GGNG guarantees packet delivery and can be extended toward a mobile sensor network in a limited 3D space. Simulations show that the path stretch of each routing protocol to GGNG in approximately 90 % of the cases is between 1.02 and 189.24. In addition, the number of messages transmitted by a node surrounding a hole in the guide construction is approximately three. Copyright © 2014 John Wiley & Sons, Ltd.     

A cluster‐based fault‐tolerant routing protocol for wireless sensor networks

Energy conservation and fault tolerance are two critical issues in the deployment of wireless sensor networks (WSNs). Many cluster‐based fault‐tolerant routing protocols have been proposed for energy conservation and network lifetime maximization in WSNs. However, these protocols suffer from high frequency of re‐clustering as well as extra energy consumption to tolerate failures and consider only some very normal parameters to form clusters without any verification of the energy sufficiency for data routing. Therefore, this paper proposes a cluster‐based fault‐tolerant routing protocol referred as CFTR. This protocol allows higher energy nodes to become Cluster Heads (CHs) and operate multiple rounds to diminish the frequency of re‐clustering. Additionally, for the sake to get better energy efficiency and balancing, we introduce a cost function that considers during cluster formation energy cost from sensor node to CH, energy cost from CH to sink, and another significant parameter, namely, number of cluster members in previous round. Further, the proposed CFTR takes care of nodes, which have no CH in their communication range. Also, it introduces a routing algorithm in which the decision of next hop CH selection is based on a cost function conceived to select routes with sufficient energy for data transfer and distribute uniformly the overall data‐relaying load among the CHs. As well, a low‐overhead algorithm to tolerate the sudden failure of CHs is proposed. We perform extensive simulations on CFTR and compare their results with those of two recent existing protocols to demonstrate its superiority in terms of different metrics.     

基于多信道协作负载均衡的WSN路由

在无线传感网络中,节点的资源限制给路由协议的设计提出了挑战。在高数据率应用场景中,带宽和存储容量成为其主要问题。为此,提出基于多信道协作负载均衡算法(M-CoLBA)的路由协议来提升网络带宽,并避免因队列溢出导致的数据包丢失。M-CoLBA协议先利用拥塞感知的动态路由度量均衡流量负载,再依据队列时延选择下一跳转发节点。实验数据表明,与单一信道路由协议(S-CoLBA)和多信道协议(M-HopCount)相比,提出的M-CoLBA协议具有较高的数据包传递率。     

Clustering‐based power‐controlled routing for mobile wireless sensor networks

This paper presents two new routing protocols for mobile sensor networks, viz. power‐controlled routing (PCR) and its enhanced version, i.e. Enhanced Power‐Controlled Routing (EPCR). In both the protocols, fixed transmission power is employed in the clustering phase but when ordinary nodes are about to send their data to their respective cluster‐heads, they change their transmission power according to their distance from their cluster‐head. While in PCR, the nodes are associated with the cluster‐head on the basis of weight, in EPCR it is done on the basis of distance. In addition to the protocols, we are suggesting a packet loss recovery mechanism for the PCR and EPCR. Both protocols work well for both mobile and static networks and are designed to achieve high network lifetime, high packet delivery ratio, and high network throughput. These protocols are extensively simulated using mass mobility model, with different speeds and different number of nodes to evaluate their performance. Simulation results show that both PCR and EPCR are successful in achieving their objectives by using variable transmission powers and smart clustering. Copyright © 2011 John Wiley & Sons, Ltd.     

A gradient‐based multiple‐path routing protocol for low duty‐cycled wireless sensor networks

Routing in a low duty‐cycled wireless sensor network (WSN) has attracted much attention recently because of the challenge that low duty‐cycled sleep scheduling brings to the design of efficient distributed routing protocols for such networks. In a low duty‐cycled WSN, a big problem is how to design an efficient distributed routing protocol, which uses only local network state information while achieving low end‐to‐end (E2E) packet delivery delay and also high packet delivery efficiency. In this paper, we study low duty‐cycled WSNs wherein sensor nodes adopt pseudorandom sleep scheduling for energy saving. The objective of this paper is to design an efficient distributed routing protocol with low overhead. For this purpose, we design a simple but efficient hop‐by‐hop routing protocol, which integrates the ideas of multipath routing and gradient‐based routing for improved routing performance. We conduct extensive simulations, and the results demonstrate the high performance of the proposed protocol in terms of E2E packet delivery latency and packet delivery efficiency as compared with existing protocols. Copyright © 2014 John Wiley & Sons, Ltd.     

A secure and low‐energy zone‐based wireless sensor networks routing protocol for pollution monitoring

Sensor networks can be used in many sorts of environments. The increase of pollution and carbon footprint are nowadays an important environmental problem. The use of sensors and sensor networks can help to make an early detection in order to mitigate their effect over the medium. The deployment of wireless sensor networks (WSNs) requires high‐energy efficiency and secures mechanisms to ensure the data veracity. Moreover, when WSNs are deployed in harsh environments, it is very difficult to recharge or replace the sensor's batteries. For this reason, the increase of network lifetime is highly desired. WSNs also work in unattended environments, which is vulnerable to different sort of attacks. Therefore, both energy efficiency and security must be considered in the development of routing protocols for WSNs. In this paper, we present a novel Secure and Low‐energy Zone‐based Routing Protocol (SeLeZoR) where the nodes of the WSN are split into zones and each zone is separated into clusters. Each cluster is controlled by a cluster head. Firstly, the information is securely sent to the zone‐head using a secret key; then, the zone‐head sends the data to the base station using the secure and energy efficient mechanism. This paper demonstrates that SeLeZoR achieves better energy efficiency and security levels than existing routing protocols for WSNs. Copyright © 2016 John Wiley & Sons, Ltd.     

无线传感器网络链路通信质量测量研究

首先分析了传统链路测量方法所存在的问题,提出了均值RSSI(接收信号强度显示)、均值LQI(链路质量显示)测量法,通过测量及计算RSSI、LQI的均值,可以较为准确地获得链路通信质量信息;其次构建了发送功率改变、硬件校准改变、周围环境改变和并发干扰等实验案例,分析了均值RSSI、均值LQI在上述案例下的测量性能,定义了链路测量灵敏度,计算了均值RSSI、均值LQI的灵敏度值,对RSSI及LQI用于链路通信质量测量和性能评估做出了全面的权衡。     

An unequal cluster-based routing protocol in wireless sensor networks

Clustering provides an effective method for prolonging the lifetime of a wireless sensor network. Current clustering algorithms usually utilize two techniques; selecting cluster heads with more residual energy, and rotating cluster heads periodically to distribute the energy consumption among nodes in each cluster and extend the network lifetime. However, they rarely consider the hot spot problem in multihop sensor networks. When cluster heads cooperate with each other to forward their data to the base station, the cluster heads closer to the base station are burdened with heavier relay traffic and tend to die much faster, leaving areas of the network uncovered and causing network partitions. To mitigate the hot spot problem, we propose an Unequal Cluster-based Routing (UCR) protocol. It groups the nodes into clusters of unequal sizes. Cluster heads closer to the base station have smaller cluster sizes than those farther from the base station, thus they can preserve some energy for the inter-cluster data forwarding. A greedy geographic and energy-aware routing protocol is designed for the inter-cluster communication, which considers the tradeoff between the energy cost of relay paths and the residual energy of relay nodes. Simulation results show that UCR mitigates the hot spot problem and achieves an obvious improvement on the network lifetime. Guihai Chen obtained his B.S. degree from Nanjing University, M. Engineering from Southeast University, and PhD from University of Hong Kong. He visited Kyushu Institute of Technology, Japan in 1998 as a research fellow, and University of Queensland, Australia in 2000 as a visiting professor. During September 2001 to August 2003, he was a visiting professor at Wayne State University. He is now a full professor and deputy chair of Department of Computer Science, Nanjing University. Prof. Chen has published more than 100 papers in peer-reviewed journals and refereed conference proceedings in the areas of wireless sensor networks, high-performance computer architecture, peer-to-peer computing and performance evaluation. He has also served on technical program committees of numerous international conferences. He is a member of the IEEE Computer Society. Chengfa Li was born 1981 and obtained his Bachelor’s Degree in mathematics in 2003 and his Masters Degree in computer science in 2006, both from Nanjing University, China. He is now a system programmer at Lucent Technologies Nanjing Telecommunication Corporation. His research interests include wireless ad hoc and sensor networks. Mao Ye was born in 1981 and obtained his Bachelor’s Degree in computer science from Nanjing University, China, in 2004. He served as a research assistant At City University of Hong Kong from September 2005 to August 2006. He is now a PhD candidate with research interests in wireless networks, mobile computing, and distributed systems. Jie Wu is a professor in the Department of Computer Science and Engineering at Florida Atlantic University. He has published more than 300 papers in various journal and conference proceedings. His research interests are in the areas of mobile computing, routing protocols, fault-tolerant computing, and interconnection networks. Dr. Wu serves as an associate editor for the IEEE Transactions on Parallel and Distributed Systems and several other international journals. He served as an IEEE Computer Society Distinguished Visitor and is currently the chair of the IEEE Technical Committee on Distributed Processing (TCDP). He is a member of the ACM, a senior member of the IEEE, and a member of the IEEE Computer Society.     

Comprehensive event based estimation of sensor node distribution strategies using classical flooding routing protocol in wireless sensor networks

We derive a new investigation for the wireless sensor networks (WSNs) when the underlying sensor node distribution strategies have strong influence on event specific communication performance. In this paper, we inclusively evaluated eight sensor network distributions namely: normal, gamma, exponential, beta, generalized inverse Gaussian, poison, Cauchy and Weibull. We designed and illustrated our proposed model with these node distributions for data dissemination. Moreover, performance evaluation matrices like sense count, receive count and receive redundant count are also evaluated. Additionally, we emphasized over the routing protocol behavior for different distribution strategies in the deployed WSN framework. Finally, simulation analysis has been carried out to prove the validity of our proposal. However, routing protocol for WSNs seems intractable to the sensor node distribution strategies when varied from one to another in the scenario.     

A reliable and energy‐efficient routing protocol for underwater wireless sensor networks

Recently, underwater wireless sensor networks (UWSNs) have attracted much research attention to support various applications for pollution monitoring, tsunami warnings, offshore exploration, tactical surveillance, etc. However, because of the peculiar characteristics of UWSNs, designing communication protocols for UWSNs is a challenging task. Particularly, designing a routing protocol is of the most importance for successful data transmissions between sensors and the sink. In this paper, we propose a reliable and energy‐efficient routing protocol, named R‐ERP²R (Reliable Energy‐efficient Routing Protocol based on physical distance and residual energy). The main idea behind R‐ERP²R is to utilize physical distance as a routing metric and to balance energy consumption among sensors. Furthermore, during the selection of forwarding nodes, link quality towards the forwarding nodes is also considered to provide reliability and the residual energy of the forwarding nodes to prolong network lifetime. Using the NS‐2 simulator, R‐ERP²R is compared against a well‐known routing protocol (i.e. depth‐based routing) in terms of network lifetime, energy consumption, end‐to‐end delay and delivery ratio. The simulation results proved that R‐ERP²R performs better in UWSNs.Copyright © 2012 John Wiley & Sons, Ltd.     

Lightweight,latency‐aware routing for data compression in wireless sensor networks with heterogeneous traffics

In many applications and scenarios, sensors have to regularly report what they monitor from the environment and quickly notify the sink node of event occurrence in the sensing field. An in‐network data reduction technique, such as data aggregation and data compression, can help diminish the amount of data sent from sensors, which not only saves the network bandwidth but also preserves sensors' energy. However, such technique does not consider packet latency because of the aggregation or compression operation. When some sensors generate regular reports in lower data rates, their packets have to spend longer time to be aggregated or compressed, resulting in higher packet delays. Besides, when events occur, the network could suffer from instant congestion due to the generation of numerous event notifications. Motivated with the aforementioned observations, the paper develops a lightweight, latency‐aware routing for data compression (L2DC) scheme to reduce packet latency when applying the compression technique, to reduce the amount of data generated from sensors. L2DC gives event notifications a higher priority over regular reports and eliminates unnecessary notifications to avoid bursty network congestion. In addition, L2DC facilitates the data compression process by allowing each sensor to determine whether to keep packets for compression locally or to send them to a neighbor to be compressed in a distributed manner. Our L2DC scheme can be easily built on most ad hoc and sensor routing protocols because it provides auxiliary redundant packet elimination and relay node selection mechanisms to reduce packet latency. By using the ad hoc on‐demand distance vector protocol as the example, simulation results demonstrate the effectiveness of the L2DC scheme. Copyright © 2015 John Wiley & Sons, Ltd.     

基于LEACH协议的无线传感器网络路由算法的改进与仿真

针对无线传感器网络中传感器能量有限的问题,从路由算法的角度出发,提出LEACH协议的低功耗改进方案.本文采用划定区域的方式对LEACH协议中的簇头选举进行改进,从而减少网络中节点分布不均匀的情况对簇头节点能量损耗所造成的影响,并使用NS-2进行协议改进前后的仿真.仿真实验结果表明,协议改进后网络生存期有效增长,能量消耗...     

Optimal power scheduling in 802.11n wireless networks for real‐time services

The growing popularity of mobile devices in our daily life demands higher throughput of wireless networks. The new communication standard 802.11n has significantly improved throughput because of the use of advanced technologies such as the multiple‐input multiple‐output communication technique. Because mobile devices are usually battery‐operated, power efficiency is critical; on the other hand, delay performance can be improved by transmitting at high power. To address the conflicting requirement of power saving and small delay, power scheduling is needed. In the past, many approaches to power scheduling have been proposed for real‐time applications, but few of them have considered complicated modes of channel state information(CSI) in multiple‐input multiple‐output. In this paper, we study this and classify the CSI into four types, namely, constant, slow fading, fast fading, and unknown. For known CSI, we propose an optimal algorithm for power scheduling. For unknown CSI, we propose an approximate algorithm based on some heuristics. To improve resource utilization, a stochastic delay‐bound method is proposed for fast‐fading condition. Simulation results demonstrate that the performance achieved by the optimal and heuristic algorithms agrees well with the analysis. Copyright © 2012 John Wiley & Sons, Ltd.     

DDRP: An efficient data‐driven routing protocol for wireless sensor networks with mobile sinks

Introduction of mobile sinks into a wireless sensor network can largely improve the network performance. However, sink mobility can cause unexpected changes of network topology, which may bring excessive protocol overhead for route maintenance and may offset the benefit from using mobile sinks. In this paper, we propose an efficient data‐driven routing protocol (DDRP) to address this problem. The design objective is to effectively reduce the protocol overhead for data gathering in wireless sensor networks with mobile sinks. DDRP exploits the broadcast feature of wireless medium for route learning. Specifically, each data packet carries an additional option recording the known distance from the sender of the packet to target mobile sink. The overhearing of transmission of such a data packet will gratuitously provide each listener a route to a mobile sink. Continuous such route‐learning among nodes will provide fresh route information to more and more nodes in the network. When no route to mobile sink is known, random walk routing simply is adopted for data packet forwarding. Simulation results show that DDRP can achieve much lower protocol overhead and longer network lifetime as compared with existing work while preserving high packet delivery ratio. Copyright © 2012 John Wiley & Sons, Ltd.     

A lifetime enhancement protocol in cluster‐based wireless sensor networks with guaranteed delay

Wireless sensor networks nowadays find application in all the fields of the world. Rare event detection is an important application in which the wireless sensor network is used. In the case of rare event detection, event of interest or the important event occurs very rarely. Battery‐powered sensor nodes are deployed to detect the event and report to the base station. Sensing and communicating the low priority events happen in major portion of the lifetime for the sensor nodes. However, if the event occurs, then it should be detected and communicated at the earliest to the base station or to the sink node. To reduce the network traffic due to low priority data, we propose a cross layered algorithm to improve the lifetime of the sensor nodes in the case of clustered architecture. In spite of the increase in the network lifetime, the time to detect and communicate to the base station is maintained as that of the traditional clustering approach. The proposed algorithm is simulated, and results show significant improvement in the lifetime of the sensor nodes with guaranteed latency. In this paper, we also suggest methods to support the latency to sensor nodes on priority basis for continuous reporting.     

无线传感器网络高可靠低维护地理路由协议

无线传感器网络地理路由协议要求节点根据少量本地路由信息将数据分组传输路由到目标节点。为了消除路由环,地理路由算法通常需要将网络拓扑平面化。然而现有的平面化算法要么假设节点的通信半径是一固定值,在实际应用中不适用;要么对每一条链路都进行检测是否有交叉链路,路由维护代价很高。针对以上问题,提出一种具有高可靠性和低维护成本的地理路由协议RPR(region partitioning-based routing),其基本思想是将网络划分为规则多边形区域,并在贪心路由失败时将多边形区域内的所有节点看作一个虚拟节点进行周边路由。多边形区域间通信能够降低平均路由路径长度,从而提高了路由的可靠性。基于区域划分的网络平面化策略不需要检测和删除相交链路,因此减少了路由维护开销。模拟实验结果显示,RPR协议比现有方法的平均路由路径长度更短,路由维护开销更低。     

无线传感器网络中的安全GEAR路由协议

GEAR路由是无线传感器网络中一种高效的位置和能量感知的地理路由协议，在抵御路由攻击方面有较好的特性，但是GEAR路由不能抵御虚假路由、女巫、选择性转发等攻击。针对该问题，提出了一种适合无线传感器网络特征的、基于位置密钥对引导模型的安全GEAR路由协议SGEAR，并对该协议进行了性能分析，分析显示在较小的系统开销下，SGEAR能有效抑制上述攻击及DoS攻击。     

Analysis of tree‐based multicast routing in wireless sensor networks with varying network metrics

Wireless ad hoc and sensor networks are emerging with advances in electronic device technology, wireless communications and mobile computing with flexible and adaptable features. Routing protocols act as an interface between the lower and higher layers of the network protocol stack. Depending on the size of target nodes, routing techniques are classified into unicast, multicast and broadcast protocols. In this article, we give analysis and performance evaluation of tree‐based multicast routing in wireless sensor networks with varying network metrics. Geographic multicast routing (GMR) and its variations are used extensively in sensor networks. Multicast routing protocols considered in the analytical model are GMR, distributed GMR, demand scalable GMR, hierarchical GMR, destination clustering GMR and sink‐initiated GMR. Simulations are given with comparative analysis based on varying network metrics such as multicast group size, number of sink nodes, average multicast latency, number of clusters, packet delivery ratio, energy cost ratio and link failure rate. Analytical results indicate that wireless sensor network multicast routing protocols operate on the node structure (such as hierarchical, clustered, distributed, dense and sparse networks) and application specific parameters. Simulations indicate that hierarchical GMR is used for generic multicast applications and that destination clustering GMR and demand scalable GMR are used for distributed multicast applications. Copyright © 2012 John Wiley & Sons, Ltd.