on the frame forwarding in peer-to-peer multimedia streaming
One of the unique features of P2P streaming is that each peer plays both client and server roles at the same time. Distribution of program streams is achieved by peer forwarding instead of providing from a set of centralized servers. Consequently, loss of a frame not only causes the peer to miss the frame, but all the descendant peers feel the effect as well. In this paper, we investigate the design issues on frame forwarding in peer-to-peer multimedia streaming. To provide smooth streaming services, we argue that the selection of a new parent peer for a child peer should consider not only network quality (e.g. delay and bandwidth), but also the frame-buffer status between the parent-child peers. When there is a large mismatch on the frame-buffer status between parent-child peers, the child peer suffers interruption during playback. We discuss the effects caused by both frame caching and peer selection. With regard to frame caching, we discuss issues of frame buffering, frame forwarding rate, frame synchronization, and old frame management schemes. With peer selection, we discuss issues of selection criteria and their impact. Two selection criteria, ALF and AUF, are discussed regarding critical conditions encountered. Based on the above different design considerations, we propose ten forwarding mechanisms for discussion and comparison. Through simulation, we show how the proposed forwarding mechanisms based on frame synchronization and aggressive old frame management schemes can effectively reduce frame loss.
frame forwarding p2p multimedia streaming frame-buffer mismatch