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One of the most important applications of wireless sensor networks is data collection. This paper proposes as efficient approach for data collection in wireless sensor networks by introducing Member Forward List. This list includes the nodes with highest priority for forwarding the data. When a node fails or dies, this list is used to select the next node with higher priority. The benefit of this node is that it prevents the algorithm from repeating when a node fails or dies. The results show that Member Forward List decreases power consumption and latency in wireless sensor networks  

The wireless sensor networks include a lot of sensor nodes with a limited energy distributed in a limited geography area. One of the important issues in these networks is the increased longevity of a network. In a wireless sensor network a long connecting distance between sensors and sink uses a lot of energy and decreases the longevity of network. Since clustering can decrease requirement of using energy for wireless sensor networks, we are following an intelligent technique for forming and managing clusters in this article. With clustering wireless sensor network and using a genetic algorithms we can decrease the connecting distance a little, so the longevity of network will be more. The... 

Wireless sensor networks (WSNs) use energy for their sensing, computation, and communication. To increase the lifetime of the network, sensor nodes are equipped with energy storage devices. Recharging of their batteries is not possible in most applications. Therefore, energy consumption needs to be monitored and limited to increase the energy consumption performance of the network. The communication module uses the highest amount of energy in a WSN. Among several methods offered to reduce the energy consumption, data compression has the highest effect on the energy usage by reducing the number of bits to be broadcasted. This paper illustrates an energy consumption reduction in WSN by... 

A large number of Wireless Sensor Network (WSN) security schemes have been proposed in the literature, relying primarily on symmetric key cryptography. To enable those, Random Key pre-Distribution (RKD) systems have been widely accepted. However, WSN nodes are vulnerable to physical compromise. Capturing one or more nodes operating with RKD would give the adversary keys to compromise communication of other benign nodes. Thus the challenge is to enhance resilience of WSN to node capture, while maintaining the flexibility and low-cost features of RKD. We address this problem, without any special-purpose hardware, proposing a new and simple idea: key splitting. Our scheme does not increase... 

A large number of random key pre-distribution (RKD) schemes have been proposed in the literature to secure wireless sensor network applications, relying on symmetric key cryptography. However, sensor nodes are exposed to physical compromise by adversaries, who target the symmetric keys stored at each node. With the stolen keys in their possession, the adversaries are then able to compromise communication links between benign nodes. Here, the big challenge arises: how to increase resilience of RKD schemes for wireless sensor networks to node capture, while maintaining the flexibility and low-cost features of RKD? We propose the idea of key splitting to address this problem, without the need... 

An effective approach for energy conservation in wireless sensor networks is scheduling sleep intervals for extraneous nodes while the remaining nodes stay active to provide continuous service. For the sensor network to operate successfully the active nodes must maintain both sensing coverage and network connectivity, It proved before if the communication range of nodes is at least twice the sensing range, complete coverage of a convex area implies connectivity among the working set of nodes. In this paper we consider a rectangular region A =a *b , such that Rs ≤ a, Rs ≤ b where Rs is the sensing range of nodes. and put a constraint on minimum allowed distance between nodes( Rs ). according... 

Most of clustered models in wireless sensor networks use a double-layered structure. In these structures a node is considered as cluster-head and has the responsibility of gathering information of environment. Static attribute is the main disadvantage of these clustering method. because as traffic rises in environment as time passes, cluster-head nodes energy and its close nodes, is consumed rapidly and so these nodes that has important role in data gathering, are break down. This issue is considered as age decrease in network life time and finally, network death. In this paper, a new three-layered dynamic model is introduced that its main goal is to increase network life time. The dynamic... 

A wireless sensor network with a large number of small sensor nodes can be used as an effective tool for gathering data in various situations. Energy is a critical resource in wireless sensor networks and system lifetime needs to be prolonged through the use of energy-aware strategies during system operation. Routing protocols in WSNs might differ depending on the application and network architecture. Many routing protocols have been specifically designed for WSNs where energy awareness is an essential design issue. The aim of this paper is to evaluate the efficiency of a routing protocol named directed flooding which is a fault-tolerant and energy efficient routing protocol for wireless... 

A wireless Ad-hoc sensor network consists of a number of sensors spread across a geographical area as a collection of sensors that form an ad-hoc wireless network. Sensors are very tiny devices that their primary function is to sense the target, convert the signal into a suitable data format, and pass on the data to a command node. These sensor nodes are very heavily constrained in processing power, and have a limited energy supply. Since energy is such a scarce resource, several algorithms have been developed at the routing and MAC layers to utilize energy efficiently and extend the lifetime of the network. First layer of the sensor networks is the infrastructure layer and there is no... 

A Wireless sensor network (WSN) is composed of numerous sensor nodes with both insecurely limited hardware and restricted communication capabilities. Thus WSNs suffer from some inherent weaknesses. Key management is an interesting subject in WSNs because it is the fundamental element for all security operations. A few key management models for heterogeneous sensor networks have been proposed in recent years. In this paper, we propose a new key management scheme based on elliptic curve cryptography and signcryption method for hierarchical heterogeneous WSNs. Our scheme as a secure infrastructure has superior sensor node mobility and network scalability. Furthermore, we propose both a periodic... 

A conventional wireless sensor network node consists of a number of components: microprocessor, memory, sensor, and radio. Advances in nanotechnology have enabled the miniaturization of these components, thus enabling wireless nanoscale sensor networks (WNSN). Due to their small size, WNSN nodes are expected to be powered by harvesting energy from the environment. Unfortunately, there is a mismatch in the energy that can be harvested and the energy required to power all the aforementioned components in a WNSN node. In this article, we propose a simplified sensor node architecture for event detection. We call our architecture Sensorless Event MONitoring in self-powered WNSNs (SEMON). A SEMON... 

In many wireless sensor network applications, nodes are mobile, while many protocols proposed for these networks assume a static network. Thus, it is important to evaluate if a traditional protocol designed for a static network can tolerate different levels of mobility. This paper provides an analytic model to investigate the effect of mobility on a well-known cluster-based protocol, LEACH. The model evaluates data loss after construction of the clusters due to node mobility, which can be used to estimate a proper update interval to balance the energy and data loss ratio. Thus, the results can help the network designer to adjust the topology update interval given a value of acceptable data... 

Localization is a crucial problem in wireless sensor networks and most of the localization algorithms given in the literature are non-adaptive and designed for fixed sensor networks. In this paper, we propose a learning based localization algorithm for mobile wireless sensor networks. By this technique, mobility in the network will be discovered by two crucial methods in the beacons: position and distance checks methods. These two methods help to have accurate localization and constrain communication just when it is necessary. The proposed method localizes the nodes based on connectivity information (hop count), which doesn't need extra hardware and is cost efficient. The experimental... 

Wireless sensor networks (WSNs) consume energy for their sensing, computation, and communication. To extend the lifetime of the network, sensor nodes are equipped with energy storage devices. Recharging of their batteries is impossible in most applications. Therefore, energy consumption needs to be monitored and limited to extend the high performance operation of the network. In this network, the communication module consumes the highest amount of energy. This paper demonstrates that among several methods offered to reduce the energy consumption, data compression has the highest effect on the energy usage by reducing the number of bits to be broadcasted. To determine the energy efficiency of... 

An effective approach for energy conservation in wireless sensor networks is scheduling sleep intervals for extraneous nodes while the remaining nodes stay active to provide continuous service. For the sensor network to operates successfully, the active nodes must maintain both sensing coverage and network connectivity. It has been proved before if the communication range of nodes is at least twice the sensing range, complete coverage of a convex area implies connectivity among the working set of nodes. In this paper first we consider a rectangular region A = a * b, such that Rs≤a, Rs≤b where Rs is the sensing range of node, and put a constraint on minimum allowed distance between nodes (... 

Many applications that utilise wireless sensor networks (WSNs) require essentially secure communication. However, WSNs suffer from some inherent weaknesses because of restricted communication and hardware capabilities. Key management is the crucial important building block for all security goals in WSNs. Most existing researches tried to assign keys assuming homogeneous network architecture. Recently, a few key management models for heterogeneous WSNs have been proposed. In this study, the authors propose a dynamic key management framework based on elliptical curve cryptography and signcryption method for heterogeneous WSNs. The proposed scheme has network scalability and sensor node (SN)... 

In this paper, after studying the demands and requirements of a perfect smart grid and specifications of network topology and sensor nodes utilized in a Wireless Sensor Network [WSN], a manipulated version of them is proposed to be combined with smart grid in order to improve the data acquisition step, increase the security and facilitate the process of information and desired commands from users. We will take the advantage of computer simulations to illustrate improved capacity and speed of this method. Finally, we will analyze the advantages of employing this proposed structure in a smart grid  

Lifetime is the mos important concern in Wireless Sensor Networks (WSNs) due to limited battery power of sensor nodes. Moreover, a WSN should be capable of timely fulfilling its mission without losing important information in event-critical applications. In this paper, we focus on designing an energy-efficient and energy-aware real-time routing algorithm aiming to explore the long lifetime routing schemes in which delay constraint is satisfied in the presence of lossy communication links. To achieve this goal, our energy-aware forwarding protocol utilizes an optimum distance real-time routing algorithm to minimize energy consumption in unreliable WSNs. Simulation results reveal that the... 

One of the arising issues in wireless sensor networks is running multiple applications to reduce deployment, administrative and management costs. In this paper we assume a sensor network in which nodes of a group have a set of same applications in their external flash memory that some of them are loaded and running. Occasionally, these applications should be updated for reasons that are manifold ranging from fixing software bugs to retasking. It is often that updates for a subset of applications happen at the same time, for example when a routing protocol shared among a subset of applications is changed. To bring the sensor nodes up to date with the new versions of the applications, existing... 

Wireless sensor networks include small nodes which have sensing ability; calculation and connection extend themselves everywhere soon. Such networks have source limitation on connection, calculation and energy consumption. So, since the nodes have limited energy in sensor networks, the optimized energy consumption in these networks is of more importance and has created many challenges. The previous works have shown that by organizing the network nodes in a number of clusters, the energy consumption could be reduced considerably. So the lifetime of the network would be increased. In this paper, we used the Queen-bee algorithm to create energy efficient clusters in wireless sensor networks....