IPTV Delivery Networks

Chapter 6Channel-Zapping Time in IPTV: Challenges and Solutions

Sajjad Zare, Seyyed Mohammad Hosseini Verki and Akbar Ghaffarpour Rahbar

6.1 Introduction

Channel-zapping time is one of the most important factors for the quality of experience (QoE) metric in IPTV services. Channel-change latency is determined as the time difference between pressing some buttons on a remote control and the moment of displaying the first frame of the ordered channel on the TV screen. In other words, the time it takes to play a new TV programme from requesting a channel change is called zapping time, which is a critical QoE metric for IPTV systems (Tian, Cheng and Shen, 2013).

Unlike analogue TVs, channel-zapping latency rises because of the requirement of audio/video data buffering, decoding at set-top box (STB) and other additional signalling information in IPTV. To guarantee interactivity and acceptable QoE, the channel-zapping latency must be under 2 s. In this chapter, we study the different methods proposed to reduce channel-zapping time in IPTV.

6.1.1 IPTV Network Infrastructure

The IPTV system structure includes four domains (Zeadally, Moustafa and Siddiqui, 2011):

• Customer domain: To present services to end-users
• Network provider domain: To provide a connection between the customer's domain and the service provider's domain
• Service provider domain: To provide services to customers
• Content provider domain: To produce content

In the following, we discuss the architecture of the basic ...