Thwarting Selfish Behavior in 802.11 WLANs

The 802.11e standard enables user configuration of several MAC parameters, making WLANs vulnerable to users that selfishly configure these parameters to gain throughput. In this paper we propose a novel distributed algorithm to thwart such selfish behavior. The key idea of the algorithm is for honest stations to react, upon detecting a selfish station, by using a more aggressive configuration that penalizes this station. We show that the proposed algorithm guarantees global stability while providing good response times. By conducting a game theoretic analysis of the algorithm based on repeated games, we also show its effectiveness against selfish stations. Simulation results confirm that the proposed algorithm optimizes throughput performance while discouraging selfish behavior. We also present an experimental prototype of the proposed algorithm demonstrating that it can be implemented on commodity hardware.Comment: 14 pages, 7 figures, journa

Authority and Incentives in Organizations

The paper analyzes the choice of organizational structure as solution to the trade-off between controlling behavior based on authority rights and minimizing costs for implementing high efforts. The analysis includes the owner of a firm, a top manager and two division heads. If it is more expensive to incentivize the division heads, the owner will prefer full delegation of authority to them to replace their high incentive pay by incentives based on private benefits of control. In that situation, decentralization is optimal given that selfish behavior is more important than cooperation for maximizing returns, but concentrated delegation of full authority to a single division head is optimal for cooperation being crucial. If, however, incentivizing the division heads is clearly less expensive than creating incentives for the top manager, the owner will choose centralization given that cooperation is the dominating issue, but partial delegation if selfish behavior is crucial

Altruism and Selfish Behavior. The Docility Model Revisited

Herbert A. Simon is widely known for his studies on rationality, artificial intelligence and for his pioneering approach to organizational studies. In one of his latest works, he presented a theory of human interaction, focused on the conflict between the selfish and the altruistic that can be seen as the essence of human relationships. The model is quite ambiguous: (1) it follows a kind of social Darwinism that (2) postulates selfish individuals’ extinction. Taking up Simon’s hypotheses on altruism, docility, and selfish behavior, we develop an alternative model of human interaction. The main objective of the paper is to show that rejecting neo-Darwinism and assuming slight complications in the model can explain more in terms of social system interactions. We assume that docility and then altruism, in a technical sense, is the basis of social interaction as it shapes the whole system. It is worth noting that, in the model, selfish individuals do not disappear.docility, altruism, social system, bounded rationality, social interactions, social Darwinism

Thwarting selfish behavior in 802.11 WLANs

The 802.11e standard enables user configuration of several MAC parameters, making WLANs vulnerable to users that selfishly configure these parameters to gain throughput. In this paper, we propose a novel distributed algorithm to thwart such selfish behavior. The key idea of the algorithm is for stations to react, upon detecting a misbehavior, by using a more aggressive configuration that penalizes the misbehaving station. We show that the proposed algorithm guarantees global stability while providing good response times. By conducting an analysis of the effectiveness of the algorithm against selfish behaviors, we also show that a misbehaving station cannot obtain any gain by deviating from the algorithm. Simulation results confirm that the proposed algorithm optimizes throughput performance while discouraging selfish behavior. We also present an experimental prototype of the proposed algorithm demonstrating that it can be implemented on commodity hardware.This work was supported by the European Community under the CROWD Project FP7-ICT-318115 and the Centro Universitario de la Defensa under Project CUD2013-05

Motivated Errors

In three sets of experiments involving 5,432 subjects, we show that agents make more errors when doing so allows them to justify selfish behavior. We show that errors relating to addition arise when they can help to justify selfishness but are eliminated when selfish motives are removed. In addition, we show that selfish motives can either exacerbate or mitigate errors relating to correlation neglect and anchoring. Our results are consistent with individuals acting confused as a justification for selfish behavior

Effect of Selfish Behavior on Power Consumption in Mobile Ad Hoc Network

A multi hop mobile ad hoc network is a peer to peer network of wireless nodes where nodes are required to perform routing activity to provide end to end connectivity among nodes. As mobile nodes are constrained by battery power and bandwidth, some nodes may behave selfishly and deny forwarding packets for other nodes, even though they expect other nodes to forward packets to keep network connected. We simulate two selfish behaviors on top of Dynamic Source Routing (DSR) protocol: the first, selfish nodes do not forward data or control packets (routing packets) for other nodes and the second, selfish nodes turn off their network interface card when they have nothing to communicate. We compare the energy saving to the selfish nodes for both the misbehaviors and show that the second selfish behavior saves more energy. This is important result because most of the cooperation enforcement mechanisms in literature, except PCOM [2], address the first selfish behavior. Also, the second selfish behavior can be easily done by layman users without any protocol level changes. Secondly, with our simulation study we find that in dense mobile ad hoc networks where route breakages are frequent, routing control packets consume significant fraction of node energy and selfish behavior by certain number of nodes reduce the overall routing overhead in network which in turn result in energy saving for both, well behaving nodes and selfish nodes

On Selfish Behavior in CSMA/CA Networks

CSMA/CA protocols rely on the random deferment of packet transmissions. Like most other protocols, CSMA/CA was designed with the assumption that the nodes would play by the rules. This can be dangerous, since the nodes themselves control their random deferment. Indeed, with the higher programmability of the network adapters, the temptation to tamper with the software or firmware is likely to grow; by doing so, a user could obtain a much larger share of the available bandwidth at the expense of other users. We use a game-theoretic approach to investigate the problem of the selfish behavior of nodes in CSMA/CA networks, specifically geared towards the most widely accepted protocol in this class of protocols, IEEE~802.11. We characterize two families of Nash equilibria in a single stage game, one of which always results in a network collapse. We argue that this result provides an incentive for cheaters to cooperate with each other. Explicit cooperation among nodes is clearly impractical. By applying the model of dynamic games borrowed from game theory, we derive the conditions for the stable and optimal functioning of a population of cheaters. We use this insight to develop a simple, localized and distributed protocol that successfully guides multiple selfish nodes to a Pareto-optimal Nash equilibrium

What's behind image? Toward a better understanding of image-driven behavior

Our experimental design systematically varies image concerns in a dictator/trust game. In comparison to the baseline, we either decrease the role of self-image concerns (by providing an excuse for selfish behavior) or increase the role of social-image concerns (by conveying the transfer choice to a third person). In this set up, we analyze the underlying processes that motivate subjects to give less/more. Controlling for distributional preferences and expectations, our results indicate that moral emotions (guilt and shame) are a significant determinant of pro-social behavior. The disposition to guilt explains giving in the baseline, while it does not when an excuse for selfish behavior exists. Subjects' disposition to shame is correlated to giving when their choice is public and they can be identified. JEL Classifications: C72, C91, D03, D8