NeTS: Medium: Collaborative Research: Modeling, Design and Emulation of P2P Real-Time Streaming Networks

新出现的趋势表明，互联网流量的很大一部分将来自实时流媒体应用。然而，考虑到任何内容的受欢迎程度的不可预测性和用户需求的显著波动，提供一个能够保证实时流所需的严格服务质量约束的集中式内容分发系统是一项非常困难的任务。因此，本项目研究以对等(P2P)方式利用终端用户资源进行实时流的建模范例和系统设计。其基本原理是P2P网络比集中式内容分发系统更容易动态地适应不断变化的网络条件和服务需求，本研究采取了整体的方法，一方面研究了对等流媒体的基本性能限制，并设计了达到这些限制的分布式算法。另一方面，我们使用这些算法作为构建块来构建实用的协议，并在仿真测试床上进行实现和验证。我们汇集了从随机过程、优化和控制理论中提取的丰富的分析工具，将它们与视频编码、丢帧和转码等现实生活中的多媒体问题以及实际实现问题结合起来。除了为日益网络化的世界开发可行的视频流想法的技术影响外，我们的项目还通过课程开发、推广和融合代表不足的群体来通知和教育学生和更广泛的社会。

Emerging trends suggest that a significant share of Internet traffic will be due to real-time streaming applications. However, given the unpredictable nature of popularity of any content and the significant swings seen in user demand, provisioning a centralized content distribution system that can guarantee the strict quality of service constraints needed for real-time streaming is a very difficult task. Therefore, this project studies modeling paradigms and systems design for utilizing end-user resources for real-time streaming in a peer-to-peer (P2P) fashion. The rationale is that P2P networks can dynamically adapt to changing network conditions and service requirements more easily than centralized content distribution systems.This research effort takes a holistic approach in which, on one hand, we study fundamental performance limits of peer-to-peer streaming and design distributed algorithms to achieve these limits. On the other hand, we use these algorithms as building blocks to construct practical protocols that are implemented and validated on an emulation testbed. We bring together a rich set of analytical tools drawn from stochastic processes, optimization and control theory to merge them with real-life multimedia issues of video coding, frame dropping and trans-coding as well as practical implementation issues. Besides the technological impact of developing viable video-streaming ideas for an increasingly networked world, our project also informs and educates both students and the broader society with curriculum development, outreach and integration of under-represented groups.