Video on demand
Video on demand is a media distribution system that allows users to access videos, television shows and films digitally on request. These multimedia are accessed without a traditional video playback device and a typical static broadcasting schedule, which was popular under traditional broadcast programming, instead involving newer modes of content consumption that have risen as Internet and IPTV technologies have become prominent, and culminated in the arrival of VOD and over-the-top media services on televisions and personal computers.
Television VOD systems can stream content, either through a traditional set-top box or through remote devices such as computers, tablets, and smartphones. VOD users may also permanently download content to a device such as a computer, digital video recorder or, a portable media player for continued viewing. The majority of cable and telecommunications company–based television providers offer VOD streaming, whereby a user selects a video programme that begins to play immediately, or downloading to a DVR rented or purchased from the provider, or to a PC or to a portable device for deferred viewing.
Streaming media has emerged as an increasingly popular medium of VOD provision over downloading, including BitTorrent. Desktop client applications such as the Apple iTunes online content store and Smart TV apps such as Amazon Prime Video allow temporary rentals and purchases of video entertainment content. Other Internet-based VOD systems provide users with access to bundles of video entertainment content rather than individual movies and shows. The most common of these systems, Netflix, Hulu, Disney+, Peacock, HBO Max and Paramount+, use a subscription model that requires users to pay a monthly fee for access to a selection of movies, television shows, and original series. In contrast, YouTube, another Internet-based VOD system, uses an advertising-funded model in which users can access most of its video content free of charge but must pay a subscription fee for premium content. Some airlines offer VOD services as in-flight entertainment to passengers through video screens embedded in seats or externally provided portable media players.
Functionality
Downloading and streaming VOD systems provide the user with features of portable media players and DVD players. Some VOD systems store and stream programs from hard-disk drives and use a memory buffer to allow the user to fast-forward and rewind videos. It is possible to put video servers on local area networks; these can provide rapid responses to users. Cable companies have rolled out their own versions of VOD services through apps, allowing television access wherever there is a device that is Internet capable. Cable media companies have combined VOD with live streaming services. The early-2020s launches of apps from cable companies are attempts to compete with subscription video on demand services because they lack live news and sports content. Streaming video servers can serve a wide community via a WAN, but responsiveness may be reduced. Download VOD services are practical in homes equipped with cable modems or DSL connections. Servers for traditional cable and telco VOD services are usually placed at the cable head-end, serving a particular market, and cable hubs in larger markets. In the telco world, they are placed in either the central office or a newly created location called a Video Head-End Office.History
VOD services first appeared in the early 1990s. Until then, it was not thought possible that a television programme could be squeezed into the limited telecommunication bandwidth of a copper telephone cable to provide a VOD service of acceptable quality as the required bandwidth of a digital television signal is around 200Mbps, which is 2,000 times greater than the bandwidth of a speech signal over a copper telephone wire.VOD services were only made possible as a result of two major technological developments:
- MPEG video compression and,
- Asymmetric digital subscriber line data transmission.
In the US, the 1982 anti-trust break-up of AT&T resulted in several smaller telephone companies nicknamed Baby Bells. Following this, the Cable Communications Policy Act of 1984 prohibited telephone companies from providing video services within their operating regions. In 1993, the National Communication and Information Infrastructure was proposed and passed by the US House and Senate, opening the way for the seven Baby Bells—Ameritech, Bell Atlantic, BellSouth, NYNEX, Pacific Telesis, Southwestern Bell, and US West—to implement VOD systems. These companies and others began holding trials to set up systems for supplying video on demand over telephone and cable lines.
In November 1992, Bell Atlantic announced a VOD trial. IBM was developing a video server code-named Tiger Shark. Concurrently, Digital Equipment Corporation was developing a scalable video server configured from small-to-large for a range of video streams. Bell Atlantic selected IBM and in April 1993 the system became the first VOD over ADSL to be deployed outside the lab, serving 50 video streams. In June 1993, US West filed for a patent to register a proprietary system consisting of the Digital Equipment Corporation Interactive Information Server, Scientific Atlanta providing the network, and 3DO as the set-top box with video streams and other information to be deployed to 2,500 homes. In 1994–95, US West filed for a patent concerning the provision of VOD in several cities: 330,000 subscribers in Denver, 290,000 in Minneapolis, and 140,000 in Portland. In early 1994, British Telecommunications introduced a trial VOD service in the United Kingdom. It used the DCT-based MPEG-1 and MPEG-2 video compression standards, along with ADSL technology.
Many VOD trials were held with various combinations of server, network, and set-top box. Of these the primary players in the US were the telephone companies using DEC, Microsoft, Oracle, IBM, Hewlett-Packard, USA Video, nCube, SGI, and other servers. The DEC server system was the most-used in these trials.
The DEC Video and Interactive Information Server architecture used a hierarchy of interactive gateways and gateway proxies to set up video streams and other information for delivery from any of a large number of VAX servers, enabling it in 1993 to support more than 100,000 streams with full videocassette recorder -like functionality. In 1994, it upgraded to a DEC Alpha–based computer for its VOD servers, allowing it to support more than a million users. By 1994 the Oracle scalable VOD system used massively parallel processors to support from 500 to 30,000 users. The SGI system supported 4,000 users. The servers connected to networks of increasing size to eventually support video stream delivery to entire cities.
In the UK, from September 1994, a VOD service formed a major part of the Cambridge Digital Interactive Television Trial. This provided video and data to 250 homes and several schools connected to the Cambridge Cable network, later part of NTL, now Virgin Media. The MPEG-1 encoded video was streamed over an ATM network from an ICL media server to set-top boxes designed by Acorn Online Media. The trial commenced at a speed of 2 Mbit/s to the home, subsequently increased to 25 Mbit/s. The content was provided by the BBC and Anglia Television. Although a technical success, difficulty in sourcing content was a major issue and the project closed in 1996.
In 1997, Enron Corporation had entered the broadband market, constructing and purchasing thousands of miles of fiber-optic cables throughout the United States. In 2001, Enron and Blockbuster Inc. attempted to create a 20-year deal to stream movies on demand over Enron's fiber-optic network. The heavily promoted deal failed, with Enron's share prices dropping following the announcement.
In 1998, Kingston Communications became the first UK company to launch a fully commercial VOD service and the first to integrate broadcast television and Internet access through a single set-top box using IP delivery over ADSL. By 2001, Kingston Interactive TV had attracted 15,000 subscribers. After several trials, Home Choice followed in 1999 but was restricted to London. After attracting 40,000 customers, they were bought by Tiscali in 2006 which was, in turn, bought by Talk Talk in 2009. Cable TV providers Telewest and NTL launched their VOD services in the United Kingdom in 2005, competing with the leading traditional pay-TV distributor BSkyB, which responded by launching Sky by broadband, later renamed Sky Anytime on PC. The service went live on 2 January 2006. Sky Anytime on PC uses a legal peer-to-peer approach based on Kontiki technology to provide very-high-capacity multi-point downloads of the video content. Instead of the video content all being downloaded from Sky's servers, the content comes from multiple users of the system who have already downloaded the content. Other UK television broadcasters implemented their own versions of the same technology, such as Channel 4's 4oD which was launched on 16 November 2006 and the BBC's iPlayer, which was launched on 25 December 2007. Another example of online video publishers using legal peer-to-peer technology is based on Giraffic technology, which was launched in early 2011, with large online VOD publishers such as US-based VEOH and UK-based Craze's Online Movies Box movie rental service.
Unlike broadcast television, which traditionally has been the most common in the form of over-the-air television, VOD systems initially required each user to have an Internet connection with considerable bandwidth to access each system's content. In 2000, the Fraunhofer Institute IIS developed the JPEG2000 codec, which enabled the distribution of movies via Digital Cinema Packages. This technology has since expanded its services from feature-film productions to include broadcast television programmes and has led to lower bandwidth requirements for VOD applications. Disney, Paramount, Sony, Universal and Warner Bros. subsequently launched the Digital Cinema Initiative, in 2002.
The BBC, ITV and Channel 4 planned to launch a joint platform provisionally called Kangaroo in 2008. This was abandoned in 2009 following complaints, which were investigated by the Competition Commission. In that same year, the assets of the now-defunct Kangaroo project were acquired by Arqiva, who used the technology to launch the SeeSaw service in February 2010. A year later, however, SeeSaw was shut down due to a lack of funding.
VOD services are now available in all parts of the United States, which has the highest global take-up rate of VOD. In 2010, 80% of American Internet users had watched video online, and 42% of mobile users who downloaded video preferred apps to a normal browser. Streaming VOD systems are available on desktop and mobile platforms from cable providers. They use the large downstream bandwidth present on their cable systems to deliver movies and television shows to end-users. These viewers can typically pause, fast-forward, and rewind VOD movies due to the low latency and random-access nature of cable technology. The large distribution of a single signal makes streaming VOD impractical for most satellite television systems. Both EchoStar/Dish Network and DirecTV offer VOD programming to PVR-owning subscribers of their satellite TV service. In Demand is a cable VOD service that also offers pay-per-view. Once the programs have been downloaded onto a user's PVR, he or she can watch, play, pause, and seek at their convenience. VOD is also common in expensive hotels.
According to the European Audiovisual Observatory, 142 paying VOD services were operational in Europe at the end of 2006. The number increased to 650 by 2009. At the 2010 Consumer Electronics Show in Las Vegas, Nevada, Sezmi CEO Buno Pati and president Phil Wiser showed a set-top box with a one-terabyte hard drive that could be used for video-on-demand services previously offered through cable television and broadband. A movie, for example, could be sent out once using a broadcast signal rather than numerous times over cable or fiber-optic lines, and this would not involve the expense of adding many miles of lines. Sezmi planned to lease part of the broadcast spectrum to offer a subscription service that National Association of Broadcasters President Gordon H. Smith said would provide a superior picture to that of cable or satellite at a lower cost.
Developing VOD requires extensive negotiations to identify a financial model that would serve both content creators and cable providers while providing desirable content for viewers at an acceptable price point. Key factors identified for determining the economic viability of the VOD model include VOD movie buy-rates and setting Hollywood and cable operator revenue splits. Cable providers offered VOD as part of digital subscription packages, which by 2005 primarily allowed cable subscribers to only access an on-demand version of the content that was already provided in the linear traditional broadcasting distribution. These on-demand packages sometimes include extras and bonus footage in addition to the regular content.