Thais Regina M. Braga

On the design of a self-managed wireless sensor network

During the last decade, there was a great technological advance in the development of smart sensors, low-power processors, and wireless communication protocols that when put together create a wireless sensor network (WSN). Smart, autonomous, and self-aware: that is the ultimate vision for WSNs. The success of this vision depends fundamentally on the self-management solutions. This work deals with this challenge: to provide a self-management solution for a WSN that monitors temperature and evaluates fire risks. We focus on self-organization, self-configuration, self-service, and self-maintenance. In particular, we propose service negotiation policies to demonstrate the self-service concept. The results reveal that the management solution can promote the productivity of network resources and the quality of the provided services.

On impact of management in wireless sensors networks

A wireless sensor network aims to collect data and, sometimes, control an environment. This kind of network is composed of hundreds to thousands of devices that have the capability of sensing, processing and wireless communicating, called sensor nodes. The sensor nodes are projected with small dimensions (cm/sup 3/ or mm/sup 3/) and this size limitation ends up restraining the node resources, like energy, processor and transceiver capacity. The task of building and deploying management systems in environments where there will be tens of thousand of network elements with particular features and organization is very complex. This task becomes worse due to the physical restrictions of these unattended sensor nodes. In this paper we have implemented and evaluated some automatic services of configuration and performance management, proposed by a WSN management architecture called MANNA. This architecture is based on the paradigm of self-management, which contains the automatic functions and services of management using a minimum of human interference. This work aims to evaluate different WSN configurations considering an application of continuous data sensing and dissemination, and the effects of the management solution proposed for this network. The built application does temperature and carbon monoxide concentration level monitoring, in an urban area. The results show the cost-benefit relations of the different organizations and demonstrates that management can promote the productivity of the resources and control the quality of the provided services.

A Tiny and Light-Weight Autonomic Element for Wireless Sensor Networks

Autonomic networks are able to monitor and control themselves without direct human intervention. The smallest unit of an autonomic network is the autonomic element (AE). This work presents the model and evaluation of a specific wireless sensor network (WSNs) AE, called autonomic sensor element (ASE). The ASE has been proposed considering WSNs hardware, software, communication and energy restrictions.

Designing a Self-organizing Wireless Sensor Network

Wireless Sensors Network are generally designed with hundreds or thousands of autonomic devices called sensor nodes. These sensor nodes organize themselves in a wireless ad hoc network that performs data sensing, processing and dissemination services. A wireless sensor network should perform, besides services related to the applications, self-management services with the goal to promote productivity and quality of service. In this work we have developed and evaluated management services related to the formation of groups and sensing area coverage maintenance, defined by the MANNA architecture, using a set of policies. The results show that this set of policies can lead to more productive sensor networks.

A Comparative Study of Distributed Self-management Approaches for Wireless Sensor Networks

The goal of a wireless sensor network (WSN) management solution is to promote network resources productivity and quality of services. This paper presents a comparative study of client/server (CS) and mobile agent (MA) approaches used in distributed self-management solutions for a hierarchical heterogeneous WSN, in which the managers are embedded into the cluster head nodes. These approaches were simulated and evaluated according to energy consumption. Considering energy consumption with transmission, the results reveal that the MA approach is more scalable than the CS one, tending to be more useful when the number of network elements and managed objects increases. On the other hand, the CS approach presents more interesting results regarding energy consumption with processing. Besides, the simulations performed also show that the MA size is an important parameter that impacts directly on the results

Service Migration in Wireless Sensor Networks

There are many approaches that can be applied to the management of wireless sensor networks (WSN) and nowadays the research in this field is only beginning. A management approach determines how the management monitor and control functions are performed by the network and network elements. Since a wireless sensor network presents severe resource constraints, a certain management approach must be chosen properly in order to optimize resource usage and at the same time satisfy the application requirements. In this paper we try to answer the following question: what is the tradeoff between to migrate management services or to adopt traditional approaches for WSN management? We have concluded from simulated and experimental results that the choice of the best approach to be adopted must consider the size of the network, the configuration of the nodes, the application goals and the management complexity, in terms of managed objects. We have also noticed that, despite the service migration approach being theoretically interesting for WSN management, for the sensor networks and sensor nodes hardware current technological situation, the approach would be applied with some negative impact on the performance of the network.