The P2P TELEVISION REVOLUTION

Informal Note :

Dr. Francis F. Muguet

15 September 2005

Introduction : We are going to study first how one has arrived to the current state of the art. Then we examine the evolution of the practices and usages which led to the formation of this new technology. Sites quoted in this informal communication are listed on the web page : http://www.p2pscience.org/tv.html

Technology: First, it should be considered that video files of important size are now downloadable between a large number of people even if one does not have a web server with a large bandwidth thanks to the BitTorrent technology.

The second point is that one can distribute the "torrents" ie metainfos according to the BitTorrent protocol as attached files to blogs, or in more technical terms as "enclosures" in RSS feeds. For those which are not familiar with blogs, which are currently very trendy in the USA, a RSS feed is a file XML which indicates the last entries on the blogs and which can be consulted by specialized readers who often recreates the look and feel of a mailing list like a newsletter. Therefore, instead of receiving information, as with email, one is retrieving periodically on a site. In addition of avoiding spam, a great advantage is that one may carry out content syndication, i.e to automatically build its own RSS feed while using filters to select items from several other RSS feeds and aggregate them.

The first idea to combine those two techniques (RSS + P2P) came in order to download automatically, with BitTorrent, video files nnounced within a RSS feed. A plugin able to read torrent files enclosed in a RSS feed is available with Azureus BitTorrent client. Then, the following step is to combine the RSS and BitTorrent technologies to give the look and feel of a Television, or more exactly a DVR (Digital Video Recorder ) both on the side of the server as well as from the perspective of the client.

Two initiatives, a commercial one ( PopCast "Open Access Internet TV"), and another non-commercial one ( Participatory Culture Foundation, GPL ) presented very recently in mid-August, the concept of Television relying on a P2P network by introducing at the same time a server (BM) and a client (DTV, beta version). One may also mention a less advanced hybrid initiative: Videora ( proprietary client / Windows ) and the corresponding open source server OpenVid.

The first innovation is that the servers must make it possible for non-technically oriented users to easily create a "television channel", i.e a RSS flow and to create torrents metafiles starting from their own video files, and to put those torrent files within the enclosures of RSS feeds. The second innovation is to provide an integrated client which, starting from those RSS feeds and the video data downloaded by P2P, is going to recreate the look and feel of a DVR like Tivo ( http://en.wikipedia.org/wiki/TiVo), or ReplayTV (http://en.wikipedia.org/wiki/ReplayTV ) i.e. convenient recording of TV programs and time-shifted viewing.

Compared to a live viewing (streaming), there will be a certain time delay due to the percolation of the file within the P2P network. This delay can to be minimal, if there is a significant number of high bandwidth seeds. In this case, BitTorrent is used mostly to implement, in a very flexible and easy way, a distributed network of servers (server grid).

Consequently the implementation of high image quality television on the Internet becomes possible among the increasing mass of the high bandwith users. Sharing the scaling feature of BitTorrent, as the number of viewers increase, so does the size of the BitTorrent swarm, and therefore access becomes better.

The fundamental point is that one does not need a web site having a very large bandwidth in order to broadcast to a significant number of viewers, quite the contrary, the more there are viewers, the better becomes the access to the content !. Consequently the creation of an Internet television channel becomes within the reach of civil society and low budget ventures. It becomes possible to create specialized channels concerning a specific audience. For example for Digital Arts, it allows the broadcast of videos of a much higher quality than streaming could provide, and furthermore one does need to rip the streams, sometimes illegally, in order to record.

Disadvantages:

1/ According to the BitTorrent protocol, one does receive (download) with a sufficient rate only if one gives (upload) in a reciprocal manner, therefore the limitation becomes the upload bandwidth which is rather small in the most current techniques ADSL and Cable affordable for the average consumer. In experiments, conducted at home, with video files of important size, and in swarms not containing a seed hosted on a high bandwith site, it was not rare that I uploaded an amount of data more than twice the amount I downloaded. Some BitTorrent clients advise users not to withdraw immediately from the swarm a recently downloaded complete file (which has become a seed), until the sharing ratio is high enough.

2/ It is a miracle participatory technology only between high bandwith users who are using with to their full extent their unused collective bandwidth. Low bandwith users are still remaining in the cold, one should be able however to implement for them lower quality channels, by using dedicated "superseeds". Further investigation will be required.

3/ Considering the latency of a BitTorrent network, it will not be easy to zap from one channel to another, except for recorded programs.

Usages : P2Ptelevision is at the crossing point of three usages or practices:

1/Digital video recorders (DVR) launched by TIVO (http://www.tivo.com), has attracted a very faithful set of customers in the United States: In this context, the rest of the world lags far behind compared to the USA. Many american enthusiasts watch TV now only with their TiVOs ( on the verge of becoming a generic name ) which allows moreover zap ads at high speed. Consequently the DTV client is simply akin to a TIVO implemented on a PC. Let us note that there are also DVR software on PC that allow to record traditional TV programs in the USA.

2/ Blogs.: After the blogs in text mode, the lasted fashion in the USA is PodCasting (because downloadable on Ipods) or audioblogs which are blogs with enclosures of audio files (mp3) which contain speech or music. There too, in comparison to the USA, the rest of the world remained behind. The following step is, of course , VideoBlog or Vlog, but since the video files are much larger important, their implementation is more confidential, even if the videos files are available not enclosed in the feed but on remote sitew. The first conference of Vloggers took place this year: VloggerCon 05 ( (22 Jan 2005, New York City, the USA). Let us underline that Vlogs are not an initiative from manufacturers but from mainstream users, not necessarily technoids. Google is, of course, very receptive to the new trend of Vlogs and has launched a beta program: Google Video Upload Program where bloggers may deposit their video contents for free. Checking the World Map of Video Blogs is telling where the action is. It becomes obvious that the next evolutionary step of Vlogs, therefore getting to P2P Television, is to replace video files with Torrent metafiles.

3/ P2P networks and BitTorrent. An Azureus plugin implements the possibility of beginning the automatic downloading of contents related to Torrents files enclosed in a RSS feed, in order to not miss the last episode of a TV series which often becomes available on the Internet within the hour. Usage of BitTorrent, in contrast, has reached a planetary scale, at least among technoids.

Concerning DVRs and Blogs, in term of usage, the USAs are in advance, compared to the remaining world, and there it is does not come as a surprise that the P2P Televisions initiatives were born in the USA.