This tutorial describes what Denial of Service (DoS) attacks are, how they can be carried out in IP networks, and how one can defend against them. Distributed DoS (DDoS) attacks are included here as a subset of DoS attacks. A DoS attack has two phases: a deployment and an attack phase. A DoS program must first be deployed on one or more compromised hosts before an attack is possible. Mitigation...

RESUMO: As helmintoses gastrintestinais constituem um dos principais fatores limitantes para a ovinocaprinocultura em todo o mundo e a saúde dos rebanhos depende de um efetivo controle antiparasitário. A resistência aos anti-helmínticos representa um dos entraves para esse controle e a busca por novas bases tem sido um desafio constante. A utilização da fitoterapia na medicina veterinária const...

In this paper we investigate denial of service (DoS) vulnerabilities in Voice over IP (VoIP) systems, focusing on the ITU-T H.323 family of protocols. We provide a simple characterisation of DoS attacks that allows us to readily identify DoS issues in H.323 protocols. We also discuss network layer DoS vulnerabilities that affect VoIP systems. A number of improvements and further research direct...

Although sulfur is an essential element for marine primary production and critical for climate processes, little is known about the oceanic pool of nonvolatile dissolved organic sulfur (DOS). We present a basin-scale distribution of solid-phase extractable DOS in the East Atlantic Ocean and the Atlantic sector of the Southern Ocean. Although molar DOS versus dissolved organic nitrogen (DON) rat...

Denial of Service (DOS) attacks are a major threat faced by all types of networks. The effect of DOS in a delay tolerant network (DTN) is even more aggravated due to the scarcity of resources. Perpetrators of DOS attacks in DTN-like environments look beyond the objective of rendering a target node useless. The aim of an attacker is to cause a network-wide degradation of resources, service and p...

The density of states (DOS) of crystalline silicon changes with the introduction of dopants due to the formation of an impurity band and band tails. Until now, the DOS of undoped silicon has been used to model silicon devices, regardless of the doping level. This approximation may not be satisfactory for the emitter and back surface field regions of silicon solar cells. Therefore, we measured t...

Currently, no reliable noninvasive methods exist for monitoring the severity of in vivo cyanide (CN) toxicity, treatment, and resulting physiological changes. We developed a broadband diffuse optical spectroscopy (DOS) system to measure bulk tissue absorption and scattering. DOS was used to optically monitor CN toxicity and treatment with sodium nitrite (NaNO2). To perform experiments, the DOS ...

Presurgical chemotherapy is widely used in the treatment of locally advanced breast cancer. Monitoring the response to therapy can improve survival and reduce morbidity. We employ a noninvasive, near-infrared method based on diffuse optical spectroscopy (DOS) to quantitatively monitor tumor response to neoadjuvant chemotherapy. DOS was used to monitor tumor response in one patient with locally ...

1PhD Professor, Department of Restorative Dentistry, São José dos Campos Dental School, UNESP, São José dos Campos, SP, Brazil. 2Chairman Professor, Department of Restorative Dentistry, Araraquara Dental School, UNESP, Araraquara, SP, Brazil. 3Chairman Professor, Department of Pathology, Bauru Dental School, University of São Paulo, USP, Bauru, SP, Brazil. 4Graduate student of Restorative Denti...