Cross-Layer Modeling of Wireless Channels: An Overview of Basic Principles

To optimize performance of applications running over wireless channels, state-of-the-art technologies incorporate a number of channel adaptation mechanisms at different layers of the protocol stack. These mechanisms affect the way communication is performed and their joint effect is often difficult to predict. Recently, to evaluate joint operation of these mechanisms, a number of cross-layer performance models have been proposed. These models abstract functionality of layers providing channel adaptation and characterize performance of information transmission at higher layers, where it is usually standardized. While cross-layer performance models differ in some details, most of them are similar in the way they approach the problem. In this paper we identify similarities between these models, formulate step-by-step cross-layer modeling procedure and discuss its basic components.