Adel Ghanbari - Digital Media Lab, Department of Computer Engineering, Sharif University of Technology
Hamid R Rabiee - Digital Media Lab, Department of Computer Engineering, Sharif University of Technology
Mohammad Khansari - Faculty of New Sciences and Technologies, University of Tehran
Mostafa Salehi - Digital Media Lab, Department of Computer Engineering, Sharif University of Technology

Using Peer-to-Peer (P2P) overlay networks havebecome a progressively popular approach for streaming livemedia over the Internet due to their deployment simplicity andscalability. In this paper, we propose a new hybrid push-pulllive P2P video streaming protocol called PPM that combinesthe benefits of pull and push mechanisms for video delivery.Our main goal is to minimize the network end-to-end delaycompared to the pure mesh networks. The PPM consists of twophases; Pull-based and Push-based. In the first phase, a newpeer joins to the network based on a pull-based mechanism.In the second phase, a parent node based on the peers’overlay hop count in the mesh topology is selected. Then, adynamic tree is constructed to push the high priority videoframes to the children of the selected parent. Using OMNET++as the simulation platform, we show that beside significantimprovement on the end-to-end delay, PPM achieves lower visualdistortion compared to the pure mesh networks. Moreover, thesimulation results confirm superiority of the PPM in comparisonwith the popular mesh-based P2P streaming systems.

Peer-to-Peer live streaming, push-pull protocol, mesh-based networks