Adjustable broadcast protocol for large-scale near-video-on-demand systems
Adjustable broadcast protocol for large-scale near-video-on-demand systems
复制标题
适用于大规模近视频点播系统的可调节广播协议
DOI：
10.1016/j.comcom.2005.01.004
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
H. Yeom
中科院分区：
文献类型：
--
作者：
J. Kwon;H. Yeom
视频点播（VOD）是一种允许客户从中央服务器选择视频节目以在电视或计算机屏幕上观看的服务。传统的单播VOD系统需要大量的服务器网络的带宽，因此已经提出了使用广播协议的准VOD系统来降低带宽需求。虽然NVOD系统可以通过广播流行视频以较少的网络带宽为多个用户提供服务，但是任何给定的视频的流行度可能随着时间的推移而变化很大，但是广播协议由于其固定的广播时间表而不能适应视频流行度分布变化的动态环境。我们介绍了一个动态的广播协议，称为可调广播（AB）的基础上在线调度，它可以调整正在使用的通道的数量上飞。AB还利用广播调度中的各种预取策略来减少所需的带宽。并且，我们提出了一个动态的信道分配方案，使用AB，最大限度地减少观众的平均等待时间。使用广泛的仿真，我们已经证明了AB的有效性和我们的动态信道分配的适应性。
Video-on-demand (VOD) is a service allowing customers to select video programs from a central server for viewing on a television or a computer screen. Traditional unicast VOD systems require huge amounts of the server network's bandwidth, so near-VOD systems using broadcast protocols have been proposed to reduce the bandwidth requirement. Although NVOD systems can service many users with less network bandwidth by broadcasting popular videos, the popularity of any given video is likely to vary widely as time goes on. However, the broadcast protocols cannot adapt to dynamic environments where the popularity distribution of videos changes, because of their fixed broadcasting schedule. We introduce a dynamic broadcast protocol called Adjustable Broadcast (AB) based on on-line scheduling, which can adjust the number of channels being used on the fly. AB also exploits various prefetching strategies in the broadcast schedule to reduce the required bandwidth. And, we propose a dynamic channel allocation scheme using AB that minimizes the average viewer's waiting time. Using extensive simulation, we have demonstrated the effectiveness of AB and the adaptability of our dynamic channel allocation.