AOM-Assisted Zapping Acceleration for IPTV

Abstract

Channel zapping time is a critical quality of experience (QoE) metric for IPTV service. Recently, zapping acceleration scheme based on time-shifted sub-channels (TSS) is introduced [1]. In this chapter, we develop a systematical analysis of TSS-based service model to understand its fundamental properties from a theoretical perspective; moreover, we propose an AOM-Assisted Zapping Acceleration (AAZA) scheme to realize TSS-based model, which improves the performance of IPTV systems. Section 5.1 briefly describes the channel zapping issue of IPTV systems and existing solutions. In Sect. 5.2, the basic principles of the TSS-based service model is presented. Section 5.3 analyzes the TSS-based model from a theoretical perspective. We show that there exists an optimal subchannel data rate which minimizes the redundant traffic transmitted over subchannels; moreover, we reveal the start-up effect, where the original operation pattern in [1] could violate the performance bound of the TSS-based model. With a convenient solution to the start-up effect proposed, we rigorously prove that the bounded zapping time is guaranteed in the TSS-based model. In Sect. 5.3, we describe the AAZA scheme to realize TSS-based model, which achieves the seamless subscriber migration from the subchannel to the main channel, without any control message exchange over the network. The subchannel selection in AAZA is independent of the zapping request signaling time, resulting in improved robustness and reduced messaging overhead. In Sect. 5.5, we implement AAZA in ns-2 and multicast an MPEG-4 video stream over a practical network topology. Extensive simulation results are presented to demonstrate the validity of our analysis and AAZA scheme. Section 5.6 summarizes this chapter.

©[2012] IEEE. Portions reprinted, with permission, from [17].