Wireless sensor networks (WSNs) have many potential applications. Furthermore, in many scenarios WSNs are of interest to adversaries and they become susceptible to some types of attacks since they are deployed in open and unprotected environments and are constituted of cheap small devices. Preventive mechanisms can be applied to protect WSNs against some types of attacks. However, there are some attacks for which there is no known prevention methods. For these cases, it is necessary to use some mechanism of intrusion detection. Besides preventing the intruder from causing damages to the network, the intrusion detection system (IDS) can acquire information related to the attack techniques, helping in the development of prevention systems. In this work we propose an IDS that fits the demands and restrictions of WSNs. Simulation results reveal that the proposed IDS is efficient and accurate in detecting different kinds of simulated attacks.

Wireless sensor networks (WSNs) are bewming an increasingly important technology that will be used in a variety of applications such as environmental monitoring, infrastructure management, public safety, medical, home and office security, transportation, and militaq. WSNs will also play a key role in pervasive computing where computing devices and people are connected to the Internet. Until now, WSNs and their applications have been developed without considering a management solution. This is a critical problem sincc nctworks comprising tens of thousands of nodes are expected to be used in some of the applications above. This article proposes the MANNA managemcnt architccture for WSNs. In particular, it prescnts the functional, information, and.physical management architectures that take into account specific characteristics of this type of network. Some of them are restrict physical resources such as energy and computing power, frequent reconfiguration and adaptation, and faults caused by nodes unavailable. The MANNA architecture considers three management dimensions: functional areas, management.levels, and WSN functionalities. These dimensions are specified to the management of a WSN and are the basis for a list of management functions, The article also proposes WSN models to guide the management activities and the use of correlation in the WSN management. This is a first step into a largely uncxplored research area.Wireless sensor networks (WSNs) provide distributed network access to sensors, actuators, and processors embedded in a variety of equipment, facilities, and the environment. A WSN represents a new monitoring and control capability for applications such as environmental monitoring, infrastructure management, public safety, medical, home and office security, transportation, and Thir work irponioliysupponed by National Research Council CNPq, Brazil. 116 0163-6804/03/$17.00 0 2003 IEEE military [l-41. A WSN combines micro elec-tromcchanical systems (MEMS) technology, new sensor materials, low-power signal processing, computation, and low-cost wireless networking in a compact system. Currently, it is possible to find sensor nodes varying from a few millimeters to 2 m. Advances during the last decade in integrated circuit technology have enabled the manufacturing of far more powerful but inexpensive sensors, radios, and processors, allowing mass production of sophisticated systems connccting the physical world to computer networksThe large use of WSNs depcnds on the design and development of a scalablc, low-cost scnsor network architecture. Such applications necd to send sensor information to users o r network entities at a l o w bit rate using low-power transceivers. Continuous scnsor signal processing . enables the constant monitoring of events in an environment in which possibly a few.data bytes would suffice. Some of the applications foreseen for WSNs will require a large number of devices on the order of tens of thousands of nodes. Traditional methods of sensor networking represent an impractical de...

Wireless Sensor Networks (WSNs) have emerged as a new monitoring and control solution for a variety of applications. Although the behavior of a WSN is characterized by the type of its application, a common element exist: faults are a normal fact, not isolated events as in traditional networks. Thus, in order to guarantee the network quality of service it is essential for the WSN to be able to detect failures and perform something akin to healing, recovering from events that might cause some of its parts to malfunction. In this work we propose and evaluate a failure detection scheme using a management architecture for WSNs, called MANNA. We take a deep look at its fault management capabilities supposing the existence of an event-driven WSN. This is a challenging and attractive kind of WSN and we show how the use of automatic management services defined by MANNA can provide self-configuration, self-diagnostic, and self-healing (some of the self-managing capabilities). We also show that the management solution promote the resources productivity without incurring a high cost to the network.

No abstract

Abstract

The air transportation network in a country has a great impact on the local, national and global economy.In this paper, we analyze the air transportation network in Brazil with complex network features to better understand its characteristics. In our analysis, we built networks composed either by national or by international flights. We also consider the network when both types of flights are put together. Interesting conclusions emerge from our analysis. For instance, Viracopos Airport (Campinas City) is the most central and connected airport on the national flights network. Any operational problem in this airport separates the Brazilian national network into six distinct subnetworks. Moreover, the Brazilian air transportation network exhibits small world characteristics and national connections network follows a power law distribution. Therefore, our analysis sheds light on the current Brazilian air transportation infrastructure, bringing a novel understanding that may help face the recent fast growth in the usage of the Brazilian transport network.

No abstract

No abstract