- This article is about Internet Protocol Television. For the television network in Iowa, see Iowa Public Television.
Internet Protocol Television (IPTV) has become a common denominator for systems where television and/or video signals are distributed to subscribers using Internet protocols. Often this is in parallel with the subscriber's Internet connection, supplied by a broadband operator using the same infrastructure and possibly bandwidth.
IPTV is not a protocol itself.
IPTV is expected to grow at a brisk pace in the coming few years as broadband is now available to more than 100 million households worldwide.
Architecture
Due to the bandwidth requirements of video, IPTV requires broadband connections to be distributed.
IPTV covers both live TV (multicasting) as well as stored video (Video on Demand VOD).
The playback of IPTV requires either a personal computer or a "set-top box" connected to a TV.
The underlying protocols used for IPTV are RSVP and HTTP.
Video Compression formats used for IPTV include MPEG-2, MPEG-4, H.264, WMV (Windows Media Video 9), and Ogg Theora.
Advantages
Advantages of IPTV include two-way capability lacked by traditional TV distribution technologies, as well as point-to-point distribution allowing each viewer to view individual broadcasts. This enables stream control (pause, wind/rewind etc.) and a free selection of programming much like its narrowband cousin, the web.
Tripleplay is an expression used by service operators describing a consumer package including telephony, data and video. Offering tripleplay on a broadband connection requires the use of IPTV and IP Telephony (Voice over IP, VoIP).
Alternatives
Alternatives to IPTV are traditional TV distribution technologies such as terrestrial, satellite and cable TV. However, cable can be upgraded to two-way capability and can thus also carry IPTV.
VOD in the US is usually delivered over cable TV using the DVB protocol and is not labelled IPTV services.
Companies
Operators
The largest operators in IPTV today are Fastweb in Italy (http://www.fastweb.it/) and Yahoo BB / Softbank in Japan.
In 2004, SBC agreed to pay Microsoft $400 million dollars for software to be used to deliver IPTV services to up to 18 million customers. Separately, SBC is investing over $4 billion USD in it's network infrastructure to prepare for the rollout.
Vendors
The term "IP/TV" is an active registered United States trademark owned first by Precept Software, Inc. and now by Cisco Systems, Inc. The IP/TV product is an audio/video system, including both servers and viewers, based on the RTP/RTCP and SDP protocols. It often uses IP multicast as well. IP/TV was introduced in 1995.
Digital broadcast equipment manufacturer Tandberg Television has a range of headend hardware and software catering to IPTV applications.
IPTV set-top box manufacturers include:
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