A wide range of P2P-based live streaming services are available online. Most are developed in China – the first streaming service of this kind to emerge to popular recognition, Coolstreaming, was released by its Chinese authors in 2002. It has been followed by other services such as PPLive, PPStream, UUSee, SopCast, TVAnts, and PPMate5.
There are two main P2PTV services which are commonly used for streaming live sporting events: SopCast and TVAnts (both of which originate in China). Streams are certainly found on other services but the key point about SopCast and TVAnts is that each allows users to create and upload their own streams. It is this ability that is a prime reason why sports fans have adopted them above others for the purpose of streaming or consuming unauthorised transmissions of live events. The online communities created and used by followers of sports encourage users to share streams and to grant access to desired events to others with the same interest. Just as a technology like bittorrent encourages users to upload to others a similar amount of content to that they have already downloaded, followers of particular teams or simply particular sports are almost always happy to actively set up a stream or at least share consumption of a stream with others.
These two primary facilitating services are discussed below, together with a list of other providers on which sporting streams also appear. First, an outline of how the typical user will locate content offered through a streaming service is outlined. Following this, the technology basis of P2P streaming services is outlined.
3.3.1 Accessing live streaming content
To demonstrate the ease with which live P2P-based streams can be accessed, this section recaps the typical user process involved in locating live streams of sporting content. As with much on the internet, the start is a Google query – in this case, for “free live sports”. As the image shows, the first result is a site called MyP2P.eu, a site offering “Free Live Sports on your PC”, including football, MLB, and NBA content:
Myp2p is a site specialized in schedules for all kind of Sports. You can watch Live Sports by using our schedules. The information we give is fully free. You only need some clients to download and then you're ready to go. Prepare to watch a lot of Football, MLB, NHL, NBA, Cricket, Tennis and many more.
The MyP2P site is one of many that collates and indexes links for live P2P-based streams. On MyP2P, these links are organised by sport and also by schedule. An automatically updated “Now Playing” list shows any event for which live streams are available at that moment.
The owners of the MyP2P site regularly inform visitors of major upcoming events – “Don't miss it, be sure to follow it!”. For instance, in early May 2008 a news post talked of the “great weekend” of sport coming up, listing baseball from the MLB and Japan; basketball from the NBA Playoffs and Spanish ACB; football from the Bundesliga, Seria A, La Liga, Premier League, playoffs in the Dutch and Greek leagues and the start of the Brazilian football season; tennis from the ATP and WTA tours; golf from the PGA and European tours; cycling from the Giro D’Italia; motorsports with the Turkish Formula One grand prix, Nascar, and GP2; ice hockey from the NHL Playoffs and IIHF World Championship; plus boxing, rugby, badminton, beachvolley, and table tennis.
 Each event listed on MyP2P – either in the ‘Now Playing’ section or when all live or upcoming events for a particular sport is selected – leads to a number of alternative live streams for the event.
For instance, choosing the Japanese baseball match at the top of the ‘Now Playing’ list above shows detail about the match and links to 7 streams re-broadcasting 2 separate channels which are showing the game live.
With the relevant software installed, clicking “Play” on any of the listed links launches the client, which connects to the SopCast tracker, contacts other viewers, and – after a short delay - begins to stream the broadcast. This process all happens without the intervention of the user. Once the P2P software has been installed once, the user simply clicks the link and everything else – from launching the software to displaying the stream – occurs without the need for user involvement.
 Like many similar sites, MyP2P also offers detailed guides on how to install and setup each piece of streaming software which may be required to view a stream. This is usually a once-only requirement – once installed, the software works automatically to recognise and broadcast the stream.
3.3.2 Technology Outline
The technical architecture behind the streaming communication used by live P2P streaming services is broadly similar across all services. In many ways, it is similar to the swarming technology used by bittorrent. Each service relies on a central server known as a ‘tracker’. The tracker organises and manages the different streams or channels available, recording and distributing information about the viewers connected to each stream – though not actually distributing any of the video content at all.
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A distributed stream first requires a video or television signal to re-broadcast. Services such as SopCast allow users to download their own broadcast software. This takes a television signal received by a tuner card into a computer – or another already existing video source – and enables the user to upload the signal to others. The software also informs the tracker that a new stream or channel is available.
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As viewers attempt to connect to that channel – after seeing a new channel appear in their client or a link posted on a portal site – their client connects to the tracker. The tracker supplies information to the client about other clients already connected to the stream.
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The client then contacts these others to request that they send parts of the video stream to other clients. This stream is split into sections of varying amounts – for example, into thirty second sections. These sections are then split further into chunks.
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The client receives chunks of each section from one or more of the others with whom it is in communication and reassembles them into the larger section, while passing the chunks to other users as requested.
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Once an entire section has been received, the client displays it to the viewer. At the same time that it is displaying this first section of the stream, the client receives the next section and if that second section of the stream is completely received by the client before the user has finished viewing the previous section, then the user notices no transition or buffering period between each section, and encounters what appears to be a seamless stream.
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