1. P2P applcations and difference from client-server
   --> No explicit client and server
   --> Democratizing content
   --> Active area of research in the early 2000s.
   --> Incentives were missing for the most part.

2. History of P2P
   --> Napster
   --> Illegal music sharing
   --> Lots of traffic
   --> Lead to shutdown

3. BitTorrent
   --> Simpler interface than Napster
   --> Torrent file, tracker server
   --> Distribute Torrent file out of band

4. Algorithms in BitTorrent
   --> The rarest first strategy
   --> Socially: ensures file is still around.
   --> Selfishly: ensures you get rare pieces before they disappear.
   --> Flip side: can't use for streaming; can't play video as it arrives
   --> Incentives: Tit-for tat

5. Why did BitTorrent fail and what did others do right?
   --> Illegal content
   --> Too much traffic
   --> No CDN mechanisms
   --> Not good for streaming video
   --> Unpredictable performance.
   --> Cheap legal alternatives
   --> Simpler UI.