HQMedia: A High Playback Quality Peer-to-Peer Live Streaming System

In Peer-to-Peer (P2P) streaming systems, media data may be lost since peers could join and leave the overlay network randomly, deteriorating the video playback quality and continuity. In this paper we develop a hybrid mesh and DHT based P2P streaming system, called HQMedia, to provide high playback quality to users by maintaining high data dissemination resilience with a low overhead. In HQMedia, peers are classified into super peers(SP) and common peers(CP) according to their online time. SPs and CPs form a mesh structure, while SPs along form a new Streaming DHT (SDHT) structure. In this hybrid architecture, we design a joint scheduling and compensation mechanism. If any frames cannot be obtained during the scheduling phase, SDHT based compensation mechanism is invoked to retrieve those missing frames near the playback point. We evaluate the performance of HQMedia by both theoretical analysis and intensive simulation experiments on large scale networks to demonstrate the effectiveness and scalability of our system. Numerical results show that HQMedia significantly outperforms existing mesh-based P2P live streaming systems by improving playback quality and continuity with only less than 1% extra maintenance overhead.