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Efekty egoistycznych ataków na poziomie MAC w sieciach ad hoc o topologii wieloskokowej

Szott Sz., Konorski J.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2016

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nr 8-9

1068--1071, CD

PL

Stacje sieci ad hoc mogą manipulować parametrami dostępu do medium transmisyjnego dla osiągnięcia nienależnie wysokiej jakości usług. Dla środowiska sieci ad hoc o topologii wieloskokowej rozważane są ataki na mechanizmy odłożenia transmisji i klasyfikacji ruchu, przeprowadzane zarówno w stosunku do przepływów źródłowych jak i tranzytowych. Wyniki pozwalają wstępnie ocenić efekty takich ataków oraz skuteczność mechanizmów obronnych.

EN

Selfish attackers in ad hoc networks can abuse MAC-layer mechanisms to achieve an undue increase of the quality of service. For a multi-hop ad hoc network we consider backoff and traffic remapping attacks, both of which can be applied either to source or transit flows. Our results provide a preliminary understanding of both the impact of these attacks as well as the performance of defense measures.

2

A Framework for Detection of Selfishness in Multihop Mobile Ad Hoc Networks

Konorski J., Orlikowski R.

Journal of Telecommunications and Information Technology

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2009

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nr 2

34-40

EN

The paper discusses the need for a fully-distributed selfishness detection mechanism dedicated for multihop wireless ad hoc networks which nodes may exhibit selfish forwarding behavior. The main contribution of this paper is an introduction to a novel approach for detecting and coping with the selfish nodes. Paper describes a new framework based on Dempster-Shafer theory-based selfishness detection framework (DST-SDF) with some mathematical background and simulation analysis.

3

IEEE 802.11 LAN capacity : incentives and incentive learning

Konorski J.

Systems Science

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2007

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Vol. 33, no 4

111-118

EN

For an ad hoc IEEE 802.11 WLAN we investigate how stations' noncooperative behavior in the form of a backoff attack (configuring small minimum and/or maximum CSMA/CA contention windows at some stations in pursuit of a large goodput share) affects a proposed realistic network capacity measure. We argue that such a measure should reflect both the total goodput and fairness, to factor in contention overhead and favor sustainable, i.e., fair, scenarios where each station pursues a large goodput share. Therefore, we consider a capacity-fairness index (CFI), the product of total goodput and the Jain index of the stations' goodput shares. If the backoff mechanism is mandatory, the CSMA/CA game that arises has a unique Nash equilibrium. In the opposite case there is no compelling outcome; we envisage that a station then calculates backoff attack incentives to predict imminent play. We link CFI to the network size, "power awareness", a stations perception of the other stations' susceptibility to incentives, and the way of learning how the stations perceive the other stations' susceptibility to incentives. We show that noncooperative behavior reduces CFI more than does contention overhead, yet if the stations are few and "power aware" enough then its impact may be lessened.