9. Chapter 9: Peer-to-peer networks

9.14. Conclusions

Peer-to-peer networks

  • Nodes are end hosts 
  • Primarily for file sharing, and recently telephony

  • Centralized directory (Napster), query flooding (Gnutella), super-nodes (KaZaA), and distributed downloading and anti-free-loading (BitTorrent)
Overlay networks
  • Tunnels between host computers
  • Hosts implement new protocols and services
  • Effective way to build networks on top of the Internet

Great example of how change can happen so quickly in application-level protocols