UHEED - an unequal clustering algorithm for wireless sensor networks

Prolonging the lifetime of wireless sensor networks has always been a determining factor when designing and deploying such networks. Clustering is one technique that can be used to extend the lifetime of sensor networks by grouping sensors together. However, there exists the hot spot problem which causes an unbalanced energy consumption in equally formed clusters. In this paper, we propose UHEED, an unequal clustering algorithm which mitigates this problem and which leads to a more uniform residual energy in the network and improves the network lifetime. Furthermore, from the simulation results presented, we were able to deduce the most appropriate unequal cluster size to be used

A Review on Hierarchical Unequal Clustering Based Protocols in Wireless Sensor Network

Wireless Sensor Networks (WSNs) are drawing attention of various researchers in the area of wireless sensing technology. The one of the major constraint on WSNs is the limited battery resources. Due to this, the routing among sensor nodes plays a vital role in reducing the energy consumption of nodes. Clustering not only provides scalability to the network, but it also balances the energy consumption among nodes according to their roles in the cluster. Equal clustering creates the problem of Hot-Spot among those nodes that have to relay the data from the farther clusters. In this paper we have studied various routing protocols which follow unequal clustering. It is found after studying these protocols that unequal clustering help tremendously in saving the energy and avoids the problem of Hot-Spot

Survey on Multi Agent Energy Efficient Clustering Algorithms in Wireless Sensor Networks

In the last few years, there are many applications for Wireless Sensor Networks (WSNs). One of the main drawbacks of these networks is the limited battery power of sensor nodes. There are many cases to reduce energy consumption in WSNs. One of them is clustering. Sensor nodes partitioned into the clusters so that one is chosen as Cluster Head (CH). Clustering and selection of the proper node as CH is very significant in reducing energy consumption and increasing network lifetime. In this paper, we have surveyed a multi agent clustering algorithms and compared on various parameters like cluster size, cluster count, clusters equality, parameters used in CHs selection, algorithm complexity, types of algorithm used in clustering, nodes location awareness, inter-cluster and intra-cluster topologies, nodes homogeneity and MAC layer communications

On demand multicast routing in wireless sensor networks

The wireless networking environment presents imposing challenges to the study of broadcasting and multicasting problems. Developing an algorithm to optimize communication amongst a group of spatially distributed sensor nodes in a WSN (Wireless Sensor Network) has been met with a number challenges due to the characterization of the sensor node device. These challenges include, but are not limited to: energy, memory, and throughput constraints. The traditional approach to overcome these challenges have emphasised the development of low power electronics, efficient modulation, coding, antenna design etc., it has been recognised that networking techniques can also have a strong impact on the energy efficiency of such systems. A variety of networking based approaches to energy efficiency are possible. One of the well-known approaches is to apply clustering techniques to effectively establish an ordered connection of sensor nodes whilst improving the overall network lifetime. This paper proposes an improved clustering based multicast approach that allows any cluster head to be a multicast source with an unlimited number of subscribers, to optimize group communication in WSNs whilst ensuring sensor nodes do not deprecate rapidly in energy levels. We review several clustering approaches and examine multicast versus broadcast communication in WSNs

On demand multicast routing in wireless sensor networks

The wireless networking environment presents imposing challenges to the study of broadcasting and multicasting problems. Developing an algorithm to optimize communication amongst a group of spatially distributed sensor nodes in a WSN (Wireless Sensor Network) has been met with a number challenges due to the characterization of the sensor node device. These challenges include, but are not limited to: energy, memory, and throughput constraints. The traditional approach to overcome these challenges have emphasised the development of low power electronics, efficient modulation, coding, antenna design etc., it has been recognised that networking techniques can also have a strong impact on the energy efficiency of such systems. A variety of networking based approaches to energy efficiency are possible. One of the well-known approaches is to apply clustering techniques to effectively establish an ordered connection of sensor nodes whilst improving the overall network lifetime. This paper proposes an improved clustering based multicast approach that allows any cluster head to be a multicast source with an unlimited number of subscribers, to optimize group communication in WSNs whilst ensuring sensor nodes do not deprecate rapidly in energy levels. We review several clustering approaches and examine multicast versus broadcast communication in WSNs

Energy aware performance evaluation of WSNs

Distributed sensor networks have been discussed for more than 30 years, but the vision of Wireless Sensor Networks (WSNs) has been brought into reality only by the rapid advancements in the areas of sensor design, information technologies, and wireless networks that have paved the way for the proliferation of WSNs. The unique characteristics of sensor networks introduce new challenges, amongst which prolonging the sensor lifetime is the most important. Energy-efficient solutions are required for each aspect of WSN design to deliver the potential advantages of the WSN phenomenon, hence in both existing and future solutions for WSNs, energy efficiency is a grand challenge. The main contribution of this thesis is to present an approach considering the collaborative nature of WSNs and its correlation characteristics, providing a tool which considers issues from physical to application layer together as entities to enable the framework which facilitates the performance evaluation of WSNs. The simulation approach considered provides a clear separation of concerns amongst software architecture of the applications, the hardware configuration and the WSN deployment unlike the existing tools for evaluation. The reuse of models across projects and organizations is also promoted while realistic WSN lifetime estimations and performance evaluations are possible in attempts of improving performance and maximizing the lifetime of the network. In this study, simulations are carried out with careful assumptions for various layers taking into account the real time characteristics of WSN. The sensitivity of WSN systems are mainly due to their fragile nature when energy consumption is considered. The case studies presented demonstrate the importance of various parameters considered in this study. Simulation-based studies are presented, taking into account the realistic settings from each layer of the protocol stack. Physical environment is considered as well. The performance of the layered protocol stack in realistic settings reveals several important interactions between different layers. These interactions are especially important for the design of WSNs in terms of maximizing the lifetime of the network

Energy Efficient data collection through Double Cluster Heads in Wireless Sensor Network

Wireless sensor network is the revolution in the sensors applicability in the modern era. Almost every sector is influenced by the wireless sensor networks. The one of the major constraint in the WSN is the limited battery resources. The efficient routing techniques have to be developed to take concern of the network lifetime. There have been various routing strategies aiming to enhance network lifetime. In this paper, we have proposed the two levels of Cluster Heads (CHs) in each cluster to make the data forwarding much efficient towards the Base Station (BS). By employing two cluster heads, the load of single CH is distributed with the other one. Main CH (MCH) will collect the data from the assistant CH (ACH) and then it will be forwarded to the BS or to the other MCH. Results in MATLAB shows that the proposed protocol has given the much enlarged network lifetime

A framework for energy based performability models for wireless sensor networks

A novel idea of alternating node operations between Active and Sleep modes in Wireless Sensor Network (WSN) has successfully been used to save node power consumption. The idea which started off as a simple implementation of a timer in most protocols has been improved over the years to dynamically change with traffic conditions and the nature of application area. Recently, use of a second low power radio transceiver to triggered Active/Sleep modes has also been made. Active/Sleep operation modes have also been used to separately model and evaluate performance and availability of WSNs. The advancement in technology and continuous improvements of the existing protocols and application implementation demands continue to pose great challenges to the existing performance and availability models. In this study the need for integrating performance and availability studies of WSNs in the presence of both channel and node failures and repairs is investigated. A framework that outlines and characterizes key models required for integration of performance and availability of WSN is in turn outlined. Possible solution techniques for such models are also highlighted. Finally it is shown that the resulting models may be used to comparatively evaluate energy consumption of the existing motes and WSNs as well as deriving required performance measures