Peers act as clients and servers, both end systems.
BITTORRENT is the most commonly used protocol as it allows fast sharing of files.
BITTORENT problems to solve?
- How does one user find another with the data which they want, to share it with them?
- How do peers replicate content to provide high-speed download for everyone?
- How do peers encourage other peers to provide content, rather than just downloading for themselves?
Solutions:
- The solution is that the content providers, must provide details of their content to the 'tracker' server. The tracker server is then able to connect users and providers together (also created a list of the 'chunks' which make up the torrent). The torrent file is at least three orders of magnitude smaller than the content it contains through compression, allowing for faster downloads. The TRACKER server contains details of all users and providers live at present and this is called the SWARM.
- Peers simultaneously upload and download CHUNKS of data. Preference is for users to download RARE chunks first which then makes them become less rare and more available then to the SWARM.
- The algorithm allows for the 'choking' of clients who only download content over time they become isolated and choked.
BITTORRENT terms and language can be esoteric though the basic principles are straightforward.