Time-Shifted Streaming in a Tree-Based Peer-to-Peer System

Abstract

Abstract-We propose a peer-to-peer (P2P) streaming system that multicasts live video as well as provides the live video as Video-on-Demand (VoD) during the live session. The proposed system allows users to individually pause and resume a live video stream, and to view video that was streamed before the particular user joined the session. Since live video content naturally results in many users watching it online at the same time, the P2P concept is leveraged to reduce server load.We extend our Stanford Peer-to-Peer Multicast (SPPM) protocol, originally designed for live video multicast, to support playback control. To achieve this in a P2P fashion, peers store received video packets in their local buffer and forward them at a later time when requested by other peers, which is called time-shifted streaming. To understand interaction between live and time-shifted traffic, we analyze video availability of the proposed system, which refers to how many peers possess video contents of a particular position. Motivated by the analysis, we propose fast prefetching and a parent selection scheme suitable for fast prefetching in order to further reduce server load by disseminating video quickly. Fast prefetching is possible because the relaxed transfer deadline of time-shifted streams and peers' extra uplink bandwidths are exploited. With simulations and mathematical analysis, it is shown that fast prefetching not only alleviates the requirement of server bandwidth by expediting video dissemination, but also mitigates video disruption due to peer churn.

Adaptive, incentive and scalable dynamic tree overlay for P2P live video streaming

“…Peers that lost connection to any of these multicast trees continue to receive other descriptions from other trees; hence the system ensures seamless streaming with a quality degradation. In these systems, video data can be partitioned into the substreams sent over different trees [9,25,29,36]. These substreams can be different descriptions, sent over the different trees such as in MDC coded video [34,46].…”

“…Mesh based systems provide high resiliency against peer churn, but also introduce high message complexity and playback lag between peers which may not be at an acceptable level for live video streaming applications. On the other hand, tree-based video streaming systems have lower playback lag and message complexity due to their structured architecture [10,26,36]; but keeping the peers connected to the tree under high peer churn is a challenging task. Hybrid mesh and tree based systems aim to make use of advantages of both mesh and tree based systems [5,9,24,25,27,29,38,45].…”

Mesh-Pull Backup Parent Pools for Video-On-Demand Multicast Trees

“…Most hybrid systems construct more than one multicast tree [22] and send different parts of the video data over those trees [25]. In figure 1, an example overlay architecture used in such systems is illustrated.…”

A path selection approach with genetic algorithm for P2P video streaming systems

“…Each peer receives video data from its parent and sends the data to its children in tree based systems [8,11,22]. Although the structural architecture of tree based systems requires low complexity in data dissemination, the performance may degrade under high peer churn [20].…”