NeTS:Small:View-Upload Decoupling: A Redesign of Multi-Channel P2P Video Systems

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。虽然有几个大规模的工业部署的点对点（P2P）直播视频系统，这些现有的系统有几个基本的性能问题，包括巨大的频道切换延迟，大的播放滞后，不太流行的频道性能差，不友好的ISP。在这些传统系统中，对等方只能重新分发它当前正在观看的视频。在这项研究中，pi正在探索一种完全不同的P2P直播视频流的方法，即观看-上传解耦（VUD）。VUD的主要思想是让每个对等点分发一个或多个频道，分配独立于对等点正在观看的内容。与传统的隔离信道设计相比，这种新方法具有三个主要优点：信道扰动抗扰性；横跨海峡的多路复用;以及结构化流媒体的启用。pi正在为多通道P2P视频流系统开发可处理的分析性能模型，用于VUD和传统设计方法。分析结果不仅突出了VUD方法的优势，而且为VUD系统的设计提供了重要的“经验法则”。pi正在开发动态VUD配置算法，这些算法既对频道流失具有鲁棒性，又能适应动态频道流行和闪电人群。网络服务供应商正在开发视频流供应、管理和流媒体方案，这些方案考虑到ISP的位置，从而大大减少了对ISP网络施加的视频流流量。pi和他们的博士生也在开发一个开源的VUD原型。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Although there are several large-scale industrial deployments of peer-to-peer (P2P) live video systems, these existing systems have several fundamental performance problems, including huge channel switching delays, large playback lags, poor performance for less-popular channels, ISP unfriendliness. In these traditional systems, a peer only redistributes the video it is currently watching. In this research, the PIs are exploring a radically different approach to P2P live video streaming, View-Upload Decoupling (VUD). The main idea of VUD is to have each peer distribute one or more channels, with the assignments being made independently of what the peer is viewing. This novel approach has three major advantages over the traditional isolated-channel designs: channel-churn immunity; cross-channel multiplexing; and the enabling of structured streaming. The PIs are developing tractable analytical performance models for multi-channel P2P video streaming systems, for both VUD and traditional design approaches. The analytical results not only highlight the advantages of the VUD approach, but also provide important ``rules-of-thumb'' for the design of VUD systems. The PIs are developing dynamic VUD provisioning algorithms that are both robust with respect to channel churn and also adapt to dynamic channel popularity and flash crowds. The PIs are developing VUD provisioning, management and streaming schemes that take into account ISP locality and largely reduce the video streaming traffic imposed on ISP networks. The PIs and their PhD students are also developing an open-source VUD prototype.