Over-the-top content (OTT) is a term used in broadcasting and technology business reporting to refer to audio, video, and other media transmitted via the Internet as a standalone product, that is, without an operator of multiple cable or direct-broadcast satellite television systems (so-called multiple-system operators) controlling or distributing the content.
In their 2008 book, Introduction to Video Search Engines, David C. Gibbon and Zhu Liu of AT&T Labs contrast an "over-the-top" method for the distribution of video on demand with video-delivery systems offered by cable and IPTV. Cable and IPTV represent tightly managed networks where channels can be changed instantly, while OTT download managers such as iTunes require that the video be downloaded first and then played. Also in 2008, the blogger Jose Miguel Consado likewise contrasted IPTV telcos and cable operators with over-the-top players such as Apple TV, Amazon Unbox or Netflix which offer movie downloads.
In 2011, the Canadian Radio-Television and Telecommunications Commission stated that it "considers that Internet access to programming independent of a facility or network dedicated to its delivery (via, for example, cable or satellite) is the defining feature of what have been termed 'over-the-top' services." 
The FCC, in its 17th Annual Assessment of the Status of Competition in the Market for the Delivery of Video Programming in 2014 (published May 2016), on developments in the video marketplace in that year, categorizes the entities providing the services into three groups:
MVPDs are defined by the FCC "based on the similarity of the video services offered," as any entity "such as, but not limited to, a cable operator, a multichannel multipoint distribution service, a direct broadcast satellite service, or a television receive-only satellite program distributor, who makes available for purchase, by subscribers or customers, multiple channels of video programming," citing Section 602(13) of the Act, and 47 U.S.C. § 522(13).:4477f The FCC notes that as of this May 2016 report date, "[t]he major MVPDs offer hundreds of linear television channels [channels that "offer video programs on a specific channel at a specific time of day"], thousands of non-linear video-on-demand (VOD) programs [that "allow consumers to select and watch video programs whenever they request them], as well as pay-per-view (PPV) programs [whether VOD and pre-scheduled special events].":4477f The matter of the means used to distribute the programming is complicated, and is a matter of a pending FCC rule chance.
An OVD is defined by the FCC as:
any entity that provides video programming by means of the Internet or other Internet Protocol (IP)-based transmission path where the transmission path is provided by a person other than the OVD. An OVD does not include an MVPD inside its MVPD footprint or an MVPD to the extent it is offering online video programming as a component of an MVPD subscription to customers whose homes are inside its MVPD footprint.
The FCC does not define the term OTT content.
In broadcasting, over-the-top content (OTT) is the audio, video, and other media content delivered over the Internet without the involvement of a multiple-system operator (MSO) in the control or distribution of the content. The Internet provider may be aware of the contents of the Internet Protocol (IP) packets but is not responsible for, nor able to control, the viewing abilities, copyrights, and/or other redistribution of the content. This model contrasts with the purchasing or rental of video or audio content from an Internet service provider (ISP), such as pay television, video on demand, and from internet protocol television (IPTV). OTT refers to content from a third party that is delivered to an end-user, with the ISP simply transporting IP packets.
OTT television remains the most popular OTT content. Access is controlled by the video distributor, through either an app or a separate OTT dongle or box, connected to a phone, PC or television set. By mid-2017, 58 per cent of US households would access one in a given month and advertising revenues from OTT channels exceeded those from web browser plug-ins.
OTT messaging is defined as instant messaging services provided by third parties, as an alternative to text messaging services provided by a mobile network operator. An example is the Facebook-owned mobile application WhatsApp, that serves to replace text messaging on Internet connected smartphones. Other providers of OTT messaging include Viber, WeChat, Skype, and Google Allo. 
OTT voice calling capabilities, for instance, as provided by Skype, WeChat, Viber, and WhatsApp use open internet communication protocols to replace and sometimes enhance existing operator controlled services offered by mobile phone operators.
Consumers can access OTT content through Internet-connected devices such as phones (including Android, iPhone, and Windows-type mobile devices), smart TVs (such as Google TV and LG Electronic's Channel Plus), set-top boxes (such as the Fire TV and Roku), gaming consoles (such as the PlayStation 4, Wii U, and Xbox One), and desktop and laptop computers and tablets.
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