Survey of Cross-layer Designs for Video Transmission Over Wireless Networks

Wireless networks are designed to enable a variety of existing and emerging multimedia streaming -applications. Multimedia streaming applications demand high quality of service (QoS), especially from wireless networks, because of the problems that exist in these types of environments, including interference, packet loss, delay, reduction of wireless link utilization, and so on. QoS necessitates the utilization of available resources at different layers of the multimedia system components, such as network, terminal, and content. Thus, a new design called cross-layer has been developed and is now considered beneficial by the research community. The aim of the current paper is to present different cross-layer designs or approaches that are classified into many categories. A cross-layer design based on the direction of information (i.e., downward, upward, hybrid, MAC-centric, and joint adaptation) and on the information itself (i.e., channel state information, QoS-related parameters, resources information, and application-based data) are also presented. In addition, a number of the video-streaming applications and their issues that cross-layer approaches attempt to solve, such as Pre-stored video streaming, real-time streaming, and congestion loss on high-definition three-dimensional television, are presented. As a result, a comparative study among the different approaches in cross-layer design is presented based on cost, QoS parameters (i.e., packet loss, delay, throughput), and complexity factors. This comparison can help in the selection of an appropriate design for the problems desired to be solved.