Spotify

= Spotify is the only on-demand music streaming service that’s not web-based. Instead, it uses a peer-to-peer network (p2p) that can scale up to meet the demands of millions of users.

Description

The Peer to Peer Network

"Spotify’s p2p network works like a BitTorrent network to locate peers (other users who have the song you want to listen to). It uses a proprietary protocol designed especially for streaming music.

There’s no “preferred” peers or supernodes, but a future improvement might be to use peer-to-peer overlays to exploit the overlap in interests between users.

The maximum number of peers in the network is 60, with a soft-limit of 50 peers.

The client uploads to at most 4 peers at a time.

Server-side trackers and network queries are used to locate other users who have the music you’re listening to. Spotify uses TCP as the transport protocol instead of UDP, since it can take advantage of TCP’s congestion controls and ability to re-send lost packets." (http://pansentient.com/2011/04/spotify-technology-some-stats-and-how-spotify-works/)