Graduation date: 2007As broadband Internet becomes widely available, Peer-to-Peer (P2P) applications over the Internet are becoming increasingly popular. Such an example is a video multicast application in which, one source streams a video to a large number of destination nodes through an overlay multicast tree consisting of peers. These overlay multicast-based applications, however, do not exploit the full band- width of every peer as the leaf nodes in the overlay multicast tree do not contribute their bandwidth to the system. On the other hand, all the peers in a properly constructed overlay mesh can contribute their bandwidth, resulting in high overall system throughput. This thesis provides details of an overlay topology that opti- mizes the bandwidth usage and also discusses design issues in node and topology management. The thesis also presents implementation details of a real world P2P system based on the above mentioned topology. Finally the designed system is deployed on machines across PlanetLab and the results are presented. Large scale simulation results are also presented to verify robustness of the system.