Peercasting
Encyclopedia
Peercasting is a method of multicast
ing streams
, usually audio and/or video, to the Internet
via peer-to-peer
technology. It can be used for commercial, independent, and amateur multicasts. Unlike traditional IP Multicast
, peercasting can facilitate on-demand
content delivery.
Another solution used is minute swarming, wherein a live stream is broken up into minute length files that are swarmed via P2P software such as BitTorrent, Coral
, or Dijjer. However, this suffers from excessive overhead for the formation of a new swarm every minute.
A new technique is to stripe a live stream into multiple substreams, akin to RAID striping. Forward error correction
and timing information is applied to these substreams such that the original stream can be reformed using at least all but one of the substreams (fountain code
s are an efficient way to make and combine the substreams). In turn, these streams are relayed using the first method.
Another solution is to permit clients to connect to a new relay and resume streaming from where they left off by their old relay. Relays would retain a back buffer to permit clients to resume streaming from anywhere within the range of said buffer. This would essentially be an extension to the Icecast
protocol.
Also, sometimes downloading BitTorrent files of TV shows is referred to as peercasting, but this usage of peercasting is not accurate.
Multicast
In computer networking, multicast is the delivery of a message or information to a group of destination computers simultaneously in a single transmission from the source creating copies automatically in other network elements, such as routers, only when the topology of the network requires...
ing streams
Streaming media
Streaming media is multimedia that is constantly received by and presented to an end-user while being delivered by a streaming provider.The term "presented" is used in this article in a general sense that includes audio or video playback. The name refers to the delivery method of the medium rather...
, usually audio and/or video, to the Internet
Internet
The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...
via peer-to-peer
Peer-to-peer
Peer-to-peer computing or networking is a distributed application architecture that partitions tasks or workloads among peers. Peers are equally privileged, equipotent participants in the application...
technology. It can be used for commercial, independent, and amateur multicasts. Unlike traditional IP Multicast
IP Multicast
IP multicast is a method of sending Internet Protocol datagrams to a group of interested receivers in a single transmission. It is often employed for streaming media applications on the Internet and private networks. The method is the IP-specific version of the general concept of multicast...
, peercasting can facilitate on-demand
Video on demand
Video on Demand or Audio and Video On Demand are systems which allow users to select and watch/listen to video or audio content on demand...
content delivery.
Operation
It usually works by having peers automatically relay a stream to other peers. The P2P network helps peers find a relay for a specified stream to connect to. This method suffers from poor quality of service during times when relays disconnect or peers need to switch to a different relay, referred to as "churn".Another solution used is minute swarming, wherein a live stream is broken up into minute length files that are swarmed via P2P software such as BitTorrent, Coral
Coral Content Distribution Network
The Coral Content Distribution Network, sometimes called Coral Cache or Coral, is a free peer-to-peer content distribution network designed and operated by Michael Freedman...
, or Dijjer. However, this suffers from excessive overhead for the formation of a new swarm every minute.
A new technique is to stripe a live stream into multiple substreams, akin to RAID striping. Forward error correction
Forward error correction
In telecommunication, information theory, and coding theory, forward error correction or channel coding is a technique used for controlling errors in data transmission over unreliable or noisy communication channels....
and timing information is applied to these substreams such that the original stream can be reformed using at least all but one of the substreams (fountain code
Fountain code
In coding theory, fountain codes are a class of erasure codes with the property that a potentially limitless sequence of encoding symbols can be generated from a given set of source symbols such that the original source symbols can ideally be recovered from any subset of the encoding symbols of...
s are an efficient way to make and combine the substreams). In turn, these streams are relayed using the first method.
Another solution is to permit clients to connect to a new relay and resume streaming from where they left off by their old relay. Relays would retain a back buffer to permit clients to resume streaming from anywhere within the range of said buffer. This would essentially be an extension to the Icecast
Icecast
Icecast is a streaming media project released as free software maintained by the Xiph.org Foundation. It also refers specifically to the server program which is part of the project. Icecast was created in December 1998/January 1999 by Jack Moffitt and Barath Raghavan to provide an open source...
protocol.
Also, sometimes downloading BitTorrent files of TV shows is referred to as peercasting, but this usage of peercasting is not accurate.
Free / Open Source
- AlluviumAlluvium (peercasting)Alluvium is open source peercasting software developed by the , first released in 2003. It comprises three components, Core, Media Player, and Server. Alluvium allows video and audio programming to be broadcast over the Internet using swarming technology...
(GPL) - FreeCastFreeCastFreeCast is a free software application which allows peer-to-peer streaming, sometimes called peercasting. It makes possible an audio or video stream broadcast to a large number of listeners from a simple DSL connection....
(GPL) - IceShare
- MediaBlogMediaBlogMediaBlog is software that distributes almost all kinds of streams on P2P network based on VLC player. The main idea of MediaBlog come from PeerCast and BitTorrent....
(GPL) - PeerCastPeerCastPeerCast is an open source streaming media multicast tool. PeerCast uses peer-to-peer technology to minimize the necessary upload bandwidth for the original multicaster.The website of PeerCast appears to be abandoned since December 2007...
(GPL) - TriblerTriblerTribler is an open source peer-to-peer client with various features for watching videos online. The user interface of Tribler is very basic and focused on ease of use, instead of including features...
(LGPL) - PulsePULSE (P2PTV)PULSE is a P2PTV application developed by the European FP7 NAPA-WINE research consortium.PULSE stands for Peer-to-Peer Unstructured Live Streaming Experiment and is a peer-to-peer live streaming system designed to operate in scenarios where the bandwidth resources of nodes can be highly...
(LGPL)
Proprietary
- OctoshapeOctoshapeOctoshape is a proprietary streaming media platform. It uses throughput optimization technology to deliver HD quality streams and to break through congestion in the last mile to provide more resilient delivery...
- RawflowRawflowRawFlow is a provider of live p2p streaming technology that enables internet broadcasting of audio and video. Rawflow was incorporated in 2002 by Mikkel Dissing, Daniel Franklin and Stephen Dicks. Its main office is in London, UK...
- Red Swoosh
- Streamer
- VeohVeohVeoh is an Internet television company based in San Diego, California. It allows users to find and watch major studio content, independent productions and user-generated material. The company is a subsidiary of Israeli start-up Qlipso....
- PPStreamPPStreamPPS.tv is a Chinese peer-to-peer streaming video network software. Since the target users are on the Chinese mainland, there is no official English version, and the vast majority of channels are from East Asia, mostly Mainland China, Korea, Japan, Hong Kong, Taiwan and Singapore...
See also
- BroadcatchingBroadcatchingBroadcatching is the downloading of digital content that has been made available over the Internet using RSS.The general idea is to use an automated mechanism to aggregate various web feeds and download content for viewing or presentation purposes....
- Comparison of streaming media systemsComparison of streaming media systemsThis is a comparison of streaming media systems. A more complete list of streaming media systems is also available.-General:The following tables compare general and technical information for a number of streaming media systems both audio and video...
- P2PTVP2PTVThe term P2PTV refers to peer-to-peer software applications designed to redistribute video streams in real time on a P2P network; the distributed video streams are typically TV channels from all over the world but may also come from other sources...
- Peer-to-peerPeer-to-peerPeer-to-peer computing or networking is a distributed application architecture that partitions tasks or workloads among peers. Peers are equally privileged, equipotent participants in the application...
- Segmented downloadingSegmented downloadingSegmented downloading can be a more efficient way of downloading files from many peers at once. The one single file is downloaded, in parallel, from several distinct sources or uploaders of the file...
- TVUnetworksTVUnetworksTVU Networks Corporation is a company that manufactures live mobile television broadcasting equipment and offers an Internet television broadcasting platform that uses P2PTV technology. Founded in 2005, the company is based in Mountain View, California.....
- Wireless ad hoc network