CHAPTER Medium Access Control Games 9.1 INTRODUCTION 9 Medium access control protocols are mechanisms that allow several users or transmitters to access a common medium or channel. They have played, and still play, an important role in the development of both wired and wireless networks. In particular, distributed protocols facilitate network deployment and allow networks to accommodate more users/transmitters without any change. An important class of protocols with contention (namely, for which there is a risk of collision) is random medium access protocols (for a classification of protocols see for example Kumar et al. (2006)). The Aloha, slotted Aloha, and CSMA (Carrier Sense Multiple Access) protocols are much used in communication networks. In the classical Aloha protocol, users can access the medium at any time, but if two or more users transmit at the same time, a collision occurs and all the packets are lost. The slotted Aloha is a variant of