Countermeasure technique to combat greedy behavior in ad-hoc wireless networks

Greedy users deviate from the IEEE 802.11 Distributed Coordination Function (DCF) standards to unfairly increase their shares of the bandwidth on the expense of other standard-abiding users. The greedy behavior is implemented by modifying the firmware of the network interface card to manipulate the back-off timer. This paper presents a methodology using non cooperative game theory to formulate a countermeasure technique to combat the greedy behavior in ad-hoc networks using proactive routing protocol. The effect of the greedy attack on the Optimized Link State Routing Protocol (OLSR) is evaluated to show the impact of the greedy behavior on the other nodes inside the network. The greedy node attempts to maximize its share of the bandwidth to increase data rate transmitted and to reduce its buffer queues and the need of retransmitting packets due to the unavailability of the bandwidth which will save resources (power and CPU processing) for the greedy node. The algorithm consists of three stages, first is to detect and identify the greedy node, then the greedy node will be temporarily isolated in the second stage. In the third stage, the greedy node will be given a second chance to join the group given that it will follow the standards. The game theory approach will consider all players (nodes) are rationale which will enable each node to review its past decisions and outcomes before making new decision.