Biblio

Flooding attacks are well-known security threats that can lead to a denial of service (DoS) in computer networks. These attacks consist of an excessive traffic generation, by which an attacker aim to disrupt or interrupt some services in the network. The impact of flooding attacks is not just about some nodes, it can be also the whole network. Many routing protocols are vulnerable to these attacks, especially those using reactive mechanism of route discovery, like AODV. In this paper, we propose a statistical approach to defense against RREQ flooding attacks in MANETs. Our detection mechanism can be applied on AODV-based ad hoc networks. Simulation results prove that these attacks can be detected with a low rate of false alerts.

Wireless mesh networks (WMNs) are attracting more and more real time applications. This kind of applications is constrained in terms of Quality of Service (QoS). Existing works in this area are mostly designed for mobile ad hoc networks, which, unlike WMNs, are mainly sensitive to energy and mobility. However, WMNs have their specific characteristics (e.g. static routers and heavy traffic load), which require dedicated QoS protocols. This paper proposes a novel traffic regulation scheme for multimedia support in WMNs. The proposed scheme aims to regulate the traffic sending rate according to the network state, based on the buffer evolution at mesh routers and on the priority of each traffic type. By monitoring the buffer evolution at mesh routers, our scheme is able to predict possible congestion, or QoS violation, early enough before their occurrence; each flow is then regulated according to its priority and to its QoS requirements. The idea behind the proposed scheme is to maintain lightly loaded buffers in order to minimize the queuing delays, as well as, to avoid congestion. Moreover, the regulation process is made smoothly in order to ensure the continuity of real time and interactive services. We use the interval type-2 fuzzy logic system (IT2 FLS), known by its adequacy to uncertain environments, to make suitable regulation decisions. The performance of our scheme is proved through extensive simulations in different network and traffic load scales.