IPTV

Television
In India, IPTV was launched by Airtel and the government service provider MTNL and BSNL through tie up with AKSH and is available in most of the major cities of the country. Reliance and Myway , Smart TV Group are also launched their services for IP TV.

Technology:
Internet Protocol television (IPTV) is a system through which television services are delivered using the Internet protocol suite over a packet-switched network such as a LAN or the Internet, instead of being delivered through traditional terrestrial, satellite signal, and cable television formats. Unlike downloaded media, IPTV offers the ability to stream the media in smaller batches, directly from the source. As a result, a client media player can begin playing the data (such as a movie) before the entire file has been transmitted. This is known as streaming media.

IPTV services may be classified into three main groups:

  • Live television, with or without interactivity related to the current TV show;
  • Time-shifted television: catch-up TV (replays a TV show that was broadcast hours or days ago), start-over TV (replays the current TV show from its beginning);
  • Video on demand (VOD): browse a catalog of videos, not related to TV programming.
  • IPTV is distinguished from Internet television by its ongoing standardization process (e.g., European Telecommunications Standards Institute) 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.

Architecture of a video server network
Depending on the network architecture of the service provider, there are two main types of video server architecture that can be considered for IPTV deployment: centralized and distributed.

The centralized architecture model is a relatively simple and easy to manage solution. For example, as all contents are stored in centralized servers, it does not require a comprehensive content distribution system. Centralized architecture is generally good for a network that provides relatively small VOD service deployment, has adequate core and edge bandwidth and has an efficient content delivery network (CDN).

Distributed architecture is just as scalable as the centralized model, however it has bandwidth usage advantages and inherent system management features that are essential for managing a larger server network. Operators who plan to deploy a relatively large system should therefore consider implementing a distributed architecture model right from the start. Distributed architecture requires intelligent and sophisticated content distribution technologies to augment effective delivery of multimedia contents over service provider’s network.

IPTV covers both live TV (multicast) as well as stored video-on-demand/VoD (unicast). Playback requires a broadband device connected to either a fixed or wireless IP network in the form of either a standalone personal computer or limited embedded OS device such as a smartphone, touch screen tablet, game console, connected TV or set-top box. Video compression is provided by either a H.263 or H.264 derived codec, audio compressed via a MDCT based codec and then encapsulated in either an MPEG transport stream or RTP packets or Flash Video packets for live or VoD streaming. IP multicasting allows for live data to be sent to multiple receivers using a single multicast group address. H.264/MPEG-4 AVC is commonly used for internet streaming over higher bit rate standards such as H.261 and H.263 which were more designed for ISDN video conferencing. H.262/MPEG-1/2 is generally not used as the bandwidth required would quite easily saturate a network which is why they are only used in single link broadcast or storage applications.

A telecommunications company IPTV service is usually delivered over an investment-heavy walled garden network.

Local IPTV, as used by businesses for audio visual AV distribution on their company networks is typically based on a mixture of:
1. Conventional TV reception equipment and IPTV encoders
2. IPTV gateways that take broadcast MPEG channels and IP wrap them to create multicast streams.

IPTV

Bandwidth capacity for simultaneously two HDTV streams, two SD streams, additional to HSD and voice