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.