Improving QoS in BitTorrent like p2p-based Video-on-Demand Systems

Among all peer-to-peer (P2P) filesharing systems, BitTorrent rises as the most prominent one. A recent analysis [1] shows that although P2P traffic is slightly declining, but BitTorrent traffic is still on the rise. It is responsible for more than 45-78% of all P2P traffic, roughly a quarter of all Internet traffic. This success has drawn a great deal of research interest on the system. In particular, there have been many lines of research studying its scalability, performance, efficiency, and fairness. In this thesis, we attempt to gain insights into the BitTorrent dynamics from a purely experimental and simulation based study. We study how heterogeneity of peer bandwidth plays a role in the overall performance of the system. Further, we investigate the application of BitTorrent protocols to Videoon-Demand systems. With the large growth of multimedia content over the internet and the ever-increasing memory space available at a cheaper cost, Video-on-demand (VoD, also called on-demand video streaming) has become an extremely popular service on the Internet. We propose topology optimization methods to achieve high performance of the networks. We verify these by extensive simulations on our home-built simulator.