Due to the enormous improvement of networking technologies and the advances in media encoding and compression techniques, IPTV becomes one of the fastest growing services in the Internet. When offered via wireless technologies (e.g., WiMAX), IPTV can pave the way for quad-play in next generation networks and ubiquitous delivery. IPTV subscribers expect the same or even better Quality of Experience (QoE) compared with the services offered by traditional operators (e.g., cable or satellite). An important QoE element is the channel switching delay also known as zapping delay. In this paper we propose a prediction-based prejoin mechanism to join one or two TV channels (which are likely to be selected next) in advance in order to shorten the channel switching time in WiMAX-based IPTV systems. A trace-driven simulation is conducted to evaluate the proposed method. The simulation results confirm the reduction of about 30% in average zapping delay.
