Dynamic Cluster Head for Lifetime Efficiency in WSN

Saving energy and increasing network lifetime are significant challenges in wireless sensor networks （WSNs）. In this paper, we propose a mechanism to distribute the responsibility of cluster-heads among the wireless sensor nodes in the same cluster based on the ZigBee standard, which is the latest WSN standard. ZigBee supports ad hoc on-demand vector （AODV） and cluster-tree routing protocols in its routing layer. However, none of these protocols considers the energy level of the nodes in the network establishing process or in the data routing process. The cluster-tree routing protocol supports single or multi-cluster networks. However, each single cluster in the multi-cluster network has only one node acting as a cluster head. These cluster-heads are fixed in each cluster during the network lifetime. Consequently, using these cluster-heads will cause them to die quickly, and the entire linked nodes to these cluster-heads will be disconnected from the main network. Therefore, the proposed technique to distribute the role of the cluster head among the wireless sensor nodes in the same cluster is vital to increase the lifetime of the network. Our proposed technique is better in terms of performance than the original structure of these protocols. It has increased the lifetime of the wireless sensor nodes, and increased the lifetime of the WSN by around 50% of the original network lifetime.

Balancing the Power Consumption Speed in Flat and Hierarchical WSN

A combination of a cluster tree routing protocol and an Ad hoc on demand vector (AODV) routing protocol is used in the latest ZigBee standard wireless sensor networks (WSNs) technology.However,the AODV routing protocol has no means by which to take into consideration the power consumption of the nodes during the routing process.Therefore,a new approach is proposed in this paper to balance the power consumption speed and to distribute the responsibilities of routing among flat wireless sensor nodes and the three levels of hierarchical wireless sensor nodes.These three levels are based on the three types of devices,which are used in the ZigBee standard:the coordinator,the routers,and the end devices.In this paper,we have compared the original AODV routing protocol with our extension approach for the distribution of power consumption.Based on the simulation results,our new approach has achieved better performance in terms of increasing the lifetime of the flat wireless sensor network,the personal area network (PAN) coordinator,the routers,and the whole network of the hierarchical wireless sensor network.Additionally,it has better performance in terms of distributing the power consumption among the key nodes of the wireless sensor network.