Enabling Future Multimedia Information Systems to Leverage Next-Generation Networking Technologies

这项研究的目的是开发一套技术，以低成本分发视频。 我们探索了一种称为动态多播的新型多播，一种称为两阶段服务模型的向家庭传送视频的巧妙方法，以及一种称为摩天大楼广播的通过卫星点播视频的有效技术。 - 动态多播旨在解决阻碍服务器充分利用网络容量的网络 I/O 瓶颈。 通过这种技术，系统能够支持比服务器物理能力多得多的同时多播。 - 摩天大楼旨在利用卫星独特的广播能力。 在这种环境下，由于带宽需求与视频数量成正比，而不是与用户数量成正比，因此我们拥有非常可扩展的技术。 就成本而言，这种方法基本上不需要布线，这一事实使其非常有吸引力。 - 第三种技术，两阶段服务模型，适用于视频播放所需比特率高于物理介质所能承受的比特率的环境。 家庭用户可以从这项技术中受益。 它为在家中搜索高分辨率视频库提供了一个非常有效的环境。 为了证明这些想法的可行性，我们实现了三个视频点播系统。 我们还使用真实视频数据进行实验来评估这些技术的性能。 有关该项目的更多信息，请访问网页：http://www.dsg.cs.ucf.edu/NSF/nsf.html。

The objective of this research is to develop a suite of techniques to allow video distribution at low cost. We explore a novel version of multicast called Dynamic Multicast, a clever way to deliver videos to homes called 2-Phase Service Model, and an efficient technique for disseminating videos on demand over satellites called Skyscraper Broadcasting. - Dynamic Multicast is designed to address the network-I/O bottleneck which hinders the server from taking full advantage of the network capacity. With this technique, the system is able to support many more simultaneous multicasts than the server is physically capable of. - Skyscraper is designed to exploit the unique broadcast capability of satellites. In this environment, since the bandwidth requirement is proportional to the number of videos, not the number of users, we have a very scalable technology. In terms of costs, the fact that this approach requires essentially no wiring makes it very appealing. - The third technique, 2-Phase Service Model, is intended for environments where the video playback requires a higher bit rate than the physical medium can sustain. Home users can benefit from this technology. It offers a very effective environment for searching high-resolution video libraries from home. To demonstrate the feasibility of these ideas, we implement three video-on-demand systems. We also conduct experiments to assess the performance of these techniques using real video data. For more information on this project, please visit the web page at http://www.dsg.cs.ucf.edu/NSF/nsf.html.