IPTV

Internet Protocol television (IPTV) is a system through which digital television service is delivered using the architecture and networking methods of the Internet Protocol Suite over a packet-switched network infrastructure, e.g., the Internet and broadband Internet access networks, instead of being delivered through traditional radio frequency broadcast, satellite signal, and cable television (CATV) formats. See Internet television.

IPTV services may be classified into three main groups: live television, time-shifted programming, and content (or video) on demand. It is distinguished from general Internet-based or web-based multimedia services by its on-going standardization process (e.g., ETSI) and preferential deployment scenarios in subscriber-based telecommunications networks with high-speed access channels into end-user premises via set-top boxes or other customer-premises equipment.

Definition

Historically, many different definitions of IPTV have appeared, including elementary streams over IP networks, transport streams over IP networks and a number of proprietary systems. Although (in Mid 2007) it is premature to say that there is a full consensus of exactly what IPTV should mean, there is no doubt that the most widely used definition today for consumer IPTV is for single or multiple program transport streams (MPTS) which are sourced by the same network operator that owns or directly controls the "last mile" to the consumer's premises. This control over delivery enables a guaranteed quality of service (QoS), and also allows the service provider to offer an enhanced user experience such as better program guide, interactive services etc.

In commercial environments IPTV is widely deployed for distribution of live TV, video playout channels and Video on Demand (VOD) material across LAN or WAN IP network infrastructures, with a controlled QoS.

The official definition approved by the International Telecommunication Union focus group on IPTV (ITU-T FG IPTV) is as follows:
"IPTV is defined as multimedia services such as television/video/audio/text/graphics/data delivered over IP based networks managed to provide the required level of quality of service and experience, security, interactivity and reliability."

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