ThrustTorrent: A Sender-Selected P2P Protocol

The popularity of video websites shows an enormous need for video sharing from individuals. We believe that P2P dissemination services, which leverage users´ upload bandwidths, will become pervasive to enable high-quality video multicasting. Though several P2P systems were proposed, we argue that a next-generation one should minimize its peer lag so that concurrent subscribers can enjoy the same home-run hit at the same time. Therefore, we mathematically examine P2P parameters, which include data dissemination time, stream data rate, data splitting degree, peer group size, etc. Then we propose a P2P protocol, named ThrustTorrent, which optimizes the diversity of available pieces among peers by merging piece and peer selections. Further, extensive packet-level simulations are performed to study the influence of control overheads. We learn that notifying peers´ downloading statuses stabilizes and enhances the overall P2P efficiency even though control overheads increase. Finally, P2P system limitations under zero peer lag are analyzed.