Wireless Networks under a Backoff Attack: A Game Theoretical Perspective

Abstract

We study a wireless sensor network using CSMA/CA in the MAC layer under a backoff attack: some of the sensors of the network are malicious and deviate from the defined contention mechanism. We use Bianchi’s network model to study the impact of the malicious sensors on the total network throughput, showing that it causes the throughput to be unfairly distributed among sensors. We model this conflict using game theory tools, where each sensor is a player. We obtain analytical solutions and propose an algorithm, based on Regret Matching, to learn the equilibrium of the game with an arbitrary number of players. Our approach is validated via simulations, showing that our theoretical predictions adjust to reality.

Repeated Game Analysis of a CSMA/CA Network under a Backoff Attack

“…In this article, we continue the work presented in Reference [8], where we studied a CSMA/CA network under a backoff attack. The network throughput was estimated using Bianchi's model [15], showing that a backoff attack did affect strongly to the network fairness, as misbehaving stations would achieve a larger portion of the network bandwidth at the expense of the stations that respected the backoff mechanism.…”

“…Indeed, CSMA is a popular choice when designing MAC protocols [6,7]. However, the deferral mechanism of CSMA/CA is vulnerable to backoff attacks, as a station may not follow the backoff procedure in order to obtain an advantage in terms of bandwidth [8].…”

“…This work includes several features from Reference [8] which were not collected in previous approaches-we use a heterogeneous network model, which takes into account different aims between different types of stations in the network. We again use Bianchi's model to estimate the effects of the bakoff on the network throughput.…”

“…We again use Bianchi's model to estimate the effects of the bakoff on the network throughput. But now, we move to repeated game solutions, whereas Reference [8] only studied static ones. Thus, we provide the next important contributions:…”

Modeling a Traffic Remapping Attack Game in a Multi-Hop Ad Hoc Network

“…At the MAC layer most attacks have found the IEEE 802.11 distributed coordination function (DCF) [16] an easy target. It has been shown in numerous studies that performing a backoff attack, i.e., changing the transmission deferment parameters (such as idle carrier sensing or backoff times) yields the attacker a considerable increase in throughput and access delays at the cost of neutral nodes [17], [18]. This type of attack has been extensively studied, though mostly in a single-hop setting which is not surprising given the single-hop nature of the MAC layer.…”