An approach to mitigate denial of service attacks in ieee 802.11 networks

Wireless networks are widely deployed and have many uses, for example in critical embedded systems. The applications of this kind of network meets the common needs of most embedded systems and addressing the particularities of each scenario, such as limitations of computing resources and energy supply. Problems such as denial of service attacks are common place and cause great inconvenience. Thus, this study presents simulations of denial of service attacks on 802.11 wireless networks using the network simulator OMNeT++. Furthermore, we present an approach to mitigate such attack, obtaining significant results for improving wireless networks.

A Dataset for Evaluating Intrusion Detection Systems in IEEE 802.11 Wireless Networks

Internet access by wireless networks has grown considerably in recent years. However, these networks are vulnerable to security problems, especially those related to denial of service attacks. Intrusion Detection Systems(IDS)are widely used to improve network security, but comparison among the several existing approaches is not a trivial task. This paper proposes building a datasetfor evaluating IDS in wireless environments. The data were captured in a real, operating network. We conducted tests using traditional IDS and achieved great results, which showed the effectiveness of our proposed approach.

Segurança em redes sem fio: estudo sobre o desenvolvimento de conjuntos de dados para comparação de IDS

Pós-graduação em Engenharia Elétrica - FEIS

Hypercapnic ventilatory response of anesthetized female rats subjected to neonatal maternal separation: Insight into the origins of panic attacks?

Neonatal maternal separation (NMS) is a form of stress that interferes with the regulation of the stress response, an effect that predisposes to the emergence of panic and anxiety related disorders. We previously showed that at adulthood, awake female (but not male) rats subjected to NMS show a hypercapnic ventilatory response (HCVR; 5% CO(2)) that is 63% greater than controls (Genest et al., 2007). To understand the mechanisms underlying the sex-specific effects of NMS on the ventilatory response to CO(2), we used two different anesthetized female rat preparations to assess central CO(2) chemosensitivity and contribution of sensory afferents (stretch receptors and peripheral chemoreceptors) that influence the HCVR. Data show that anesthesia eliminated the respiratory phenotype observed previously in awake females and CO(2) chemosensitivity did not differ between groups. Finally, the assessment of the ovarian hormone levels across the oestrus cycle failed to reveal significant differences between groups. Since anesthesia did not affect the manifestation of NMS-related respiratory dysfunction in males (including the hypercapnic ventilatory response) (Kinkead et al., 2005; Dumont and Kinkead, 2010), we propose that the panic or anxiety induced by CO(2) during wakefulness is responsible for enhancement of the HCVR in NMS females. (C) 2011 Elsevier B.V. All rights reserved.

Quality of service control for rt-VBR connections in ATM networks

Nowadays, networks must support applications such as: distance learning, electronic commerce, access to Internet, Intranets and Extranets, voice over IP (Internet Protocol) and many others. These new applications, employing data, voice, and video traffic, require high bandwidth and Quality of Service (QoS). The ATM (Asynchronous Transfer Mode) technology, together with dynamic resource allocation methods, offers network connections that guarantee QoS parameters, such as minimum losses and delays. This paper presents a system that uses Network Management Functions together with dynamic resource allocation for provision of the end-to-end QoS parameters for rt-VBR connections.

Wireless mesh networks planning based on parameters of quality of service

The use of QoS parameters to evaluate the quality of service in a mesh network is essential mainly when providing multimedia services. This paper proposes an algorithm for planning wireless mesh networks in order to satisfy some QoS parameters, given a set of test points (TPs) and potential access points (APs). Examples of QoS parameters include: probability of packet loss and mean delay in responding to a request. The proposed algorithm uses a Mathematical Programming model to determine an adequate topology for the network and Monte Carlo simulation to verify whether the QoS parameters are being satisfied. The results obtained show that the proposed algorithm is able to find satisfactory solutions.

Proposta de uma ferramenta de visualização e realidade virtual para o monitoramento de tráfego de redes de computadores

Pós-graduação em Ciência da Computação - IBILCE

Análise de eventos de segurança em redes de computadores utilizando detecção de novidade

Pós-graduação em Ciência da Computação - IBILCE

A framework for monitoring and runtime recovery of web service-based applications

Service provisioning is a challenging research area for the design and implementation of autonomic service-oriented software systems. It includes automated QoS management for such systems and their applications. Monitoring, Diagnosis and Repair are three key features of QoS management. This work presents a self-healing Web service-based framework that manages QoS degradation at runtime. Our approach is based on proxies. Proxies act on meta-level communications and extend the HTTP envelope of the exchanged messages with QoS-related parameter values. QoS Data are filtered over time and analysed using statistical functions and the Hidden Markov Model. Detected QoS degradations are handled with proxies. We experienced our framework using an orchestrated electronic shop application (FoodShop).

The correlation between subordinate fish eye colour and received attacks: a negative social feedback mechanism for the reduction of aggression during the formation of dominance hierarchies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Attacks by jaguars (Panthera onca) on humans in central Brazil: Report of three cases, with observation of a death

Conflicts between humans and big cats have been known for centuries throughout the world, but have intensified in recent decades. Recently, attacks by Panthera onca on humans in Brazil have been brought to the forefront through exposure in the press and because of the severity of the attacks. We report 3 cases of patients attacked by jaguars in provoked and predatory situations. Two patients survived the attacks and one died. Attack mechanisms and lesions in victims are discussed. The attacks demonstrate a real risk of accidents from jaguars in certain regions, such as the Pantanal and the Amazon. © 2011 Wilderness Medical Society.