9 research outputs found
Real-Time Misbehavior Detection in IEEE 802.11e Based WLANs
The Enhanced Distributed Channel Access (EDCA) specification in the IEEE
802.11e standard supports heterogeneous backoff parameters and arbitration
inter-frame space (AIFS), which makes a selfish node easy to manipulate these
parameters and misbehave. In this case, the network-wide fairness cannot be
achieved any longer. Many existing misbehavior detectors, primarily designed
for legacy IEEE 802.11 networks, become inapplicable in such a heterogeneous
network configuration. In this paper, we propose a novel real-time hybrid-share
(HS) misbehavior detector for IEEE 802.11e based wireless local area networks
(WLANs). The detector keeps updating its state based on every successful
transmission and makes detection decisions by comparing its state with a
threshold. We develop mathematical analysis of the detector performance in
terms of both false positive rate and average detection rate. Numerical results
show that the proposed detector can effectively detect both contention window
based and AIFS based misbehavior with only a short detection window.Comment: Accepted to IEEE Globecom 201
Secure Routing and Medium Access Protocols inWireless Multi-hop Networks
While the rapid proliferation of mobile devices along with the tremendous growth of various applications using
wireless multi-hop networks have significantly facilitate our human life, securing and ensuring high quality
services of these networks are still a primary concern. In particular, anomalous protocol operation in wireless
multi-hop networks has recently received considerable attention in the research community. These relevant security
issues are fundamentally different from those of wireline networks due to the special characteristics of
wireless multi-hop networks, such as the limited energy resources and the lack of centralized control. These issues
are extremely hard to cope with due to the absence of trust relationships between the nodes.
To enhance security in wireless multi-hop networks, this dissertation addresses both MAC and routing layers
misbehaviors issues, with main focuses on thwarting black hole attack in proactive routing protocols like OLSR,
and greedy behavior in IEEE 802.11 MAC protocol. Our contributions are briefly summarized as follows.
As for black hole attack, we analyze two types of attack scenarios: one is launched at routing layer, and the
other is cross layer. We then provide comprehensive analysis on the consequences of this attack and propose
effective countermeasures.
As for MAC layer misbehavior, we particularly study the adaptive greedy behavior in the context of Wireless
Mesh Networks (WMNs) and propose FLSAC (Fuzzy Logic based scheme to Struggle against Adaptive Cheaters)
to cope with it. A new characterization of the greedy behavior in Mobile Ad Hoc Networks (MANETs) is also
introduced. Finally, we design a new backoff scheme to quickly detect the greedy nodes that do not comply with
IEEE 802.11 MAC protocol, together with a reaction scheme that encourages the greedy nodes to become honest
rather than punishing them
Secure Routing and Medium Access Protocols inWireless Multi-hop Networks
While the rapid proliferation of mobile devices along with the tremendous growth of various applications using
wireless multi-hop networks have significantly facilitate our human life, securing and ensuring high quality
services of these networks are still a primary concern. In particular, anomalous protocol operation in wireless
multi-hop networks has recently received considerable attention in the research community. These relevant security
issues are fundamentally different from those of wireline networks due to the special characteristics of
wireless multi-hop networks, such as the limited energy resources and the lack of centralized control. These issues
are extremely hard to cope with due to the absence of trust relationships between the nodes.
To enhance security in wireless multi-hop networks, this dissertation addresses both MAC and routing layers
misbehaviors issues, with main focuses on thwarting black hole attack in proactive routing protocols like OLSR,
and greedy behavior in IEEE 802.11 MAC protocol. Our contributions are briefly summarized as follows.
As for black hole attack, we analyze two types of attack scenarios: one is launched at routing layer, and the
other is cross layer. We then provide comprehensive analysis on the consequences of this attack and propose
effective countermeasures.
As for MAC layer misbehavior, we particularly study the adaptive greedy behavior in the context of Wireless
Mesh Networks (WMNs) and propose FLSAC (Fuzzy Logic based scheme to Struggle against Adaptive Cheaters)
to cope with it. A new characterization of the greedy behavior in Mobile Ad Hoc Networks (MANETs) is also
introduced. Finally, we design a new backoff scheme to quickly detect the greedy nodes that do not comply with
IEEE 802.11 MAC protocol, together with a reaction scheme that encourages the greedy nodes to become honest
rather than punishing them
Concevoir une stratégie de défense face aux comportements égoïstes de noeuds utilisant le protocole MAC IEEE 802.11
La coopération de l’ensemble des noeuds d’un réseau ad-hoc permet de garantir le fonctionnement optimal de celui-ci. Un noeud peut toutefois avoir un comportement égoïste au niveau de la sous-couche MAC du protocole IEEE 802.11 qui gère le contrôle de l’accès au médium. Ce comportement égoïste peut se traduire par une diminution de la taille de la fenêtre de contention afin d’augmenter la priorité d’émission. La conséquence d’un tel comportement pour un noeud est une amélioration de sa capacité d’émission, de son débit, entrainant une dégradation de la bande passante de l’ensemble du réseau.
Dans cette étude nous concevons une stratégie de défense basée sur la stratégie Tit-for-Tat (TFT), développée en théorie des jeux pour faire face à ces comportements égoïstes. Nous démontrerons pourquoi et comment une telle stratégie vise à obtenir l’équité dans le partage de la bande passante. Nous introduirons des variantes de TFT comme un Tit-for-Tat généreux (GTFT), où l’introduction d’un facteur de générosité va permettre de s’adapter aux contraintes du médium. Enfin nous discuterons du choix et de l’influence des paramètres d’une telle stratégie sur le comportement d’un noeud et du réseau
Algorithmes incitifs pour le partage de ressources dans les réseaux 802.11 en présence de noeuds égoïstes
La présence des noeuds égoïstes dans les réseaux 802.11 est un problème d’importance car leurs comportements peuvent être nuisible à tous. La détection des noeuds égoïstes permet d’identifier la source du problème. Ensuite, puisque la détection seule n’empêche rien, des actions doivent être entreprises contre les noeuds égoïstes. Ces actions ont pour but de faire cesser ces comportements égoïstes. Dans le cas d’un noeud égoïste qui est rationnel, ses punitions reçues contre ses comportements égoïstes devraient l’inciter à redevenir collaboratif.
Dans le cadre de cette étude, les noeuds dit égoïstes ont modifié leur implémentation de la norme 802.11. Des périodes de retrait plus courtes sont attendues par les noeuds égoïstes, ce qui leurs donnent des avantages en terme de débits de données transférés.
Pour contrer ce problème, des algorithmes de détection et de réaction contre les noeuds égoïstes sont développés