DCF/RCB: A new method for detection and punishment of selfish nodes in IEEE 802.11

Abstract

The IEEE 802.11 standard protocol is one of the most popular standards for wireless networks and its widespread and growing use has led to numerous studies on its performance and improvement of its different mechanisms. The media access mechanism used in this protocol is designed with the assumption that all users will fully comply with its rules so it doesn’t contain any approach for prevention and detection of any violation of the protocol that is called misbehavior. Selfish node misbehaves to obtain more network resources and this misbehavior can cause the loss of fairness among hosts and great reduction in the overall network performance. Among different misbehavior, waiting for a smaller backoff period against other nodes is an efficient way to gain much more throughput in the network. Different methods have been proposed so far but all of them share some defects and have some limiting factors. We study backoff misbehavior in this paper and a new mechanism called DCF/RCB containing detection and punishment methods is presented to overcome this misbehavior. The mechanism is based on a new method of assigning backoff, using a deterministic pseudo random function. It can be shown that the proposed mechanism is resilient to colluding nodes and has not some limiting factors in previous proposed schemes. Simulation results are presented to show the success of our proposed mechanism in the presence of backoff misbehavior model.