CAREER: Traffic Characterization and Resource Allocation for Transporting Video Streams Over Broadband Networks

宽带网络被设计成传输具有不同服务质量（QoS）要求的各种流量流。这些流的准确表征对于设计有效的资源分配策略至关重要，这些策略可以保证在不充分利用网络容量的情况下提供可接受的QoS。这个项目的重点是压缩视频流量的特征和研究在计算机网络上传输视频流量的资源分配方案。VBR视频流的新流量模型将在三种紧密相关的压缩算法下开发：JPEG、MPEG-1和MPEG-2。建模方法将基于M/G/infinity流程类，其通用性将被用于捕获各种形式的流量相关性。视频源（单个和聚合）将在入口节点和与其他流（即来自多路复用器的出发流量）进行多路复用后进行特征化。对分层编码的MPEG-2视频的各层模型进行了开发。将研究视频模型下的多路复用性能。将制定相应的宽带网络视频传输资源分配策略。研究了视频流量下相关性持久性对队列性能的影响。本文将研究由多个MPEG-2输入流馈送的多路复用器的几种优先级调度策略。与拟议的研究计划相联系，将追求几个教育目标。将编制关于宽频多媒体网络的新课程，这些课程将纳入PI研究议程的几个方面。这些课程的教学方法将是理论与实践的平衡结合，并将课堂教学与研究型学期项目相结合，从而使学生（研究生和大四本科生）接触到有趣的研究领域。团队合作将在课程项目中得到强烈鼓励，因为它为学生未来的工业工作环境做准备。为了扩大与工业的联系，PI教授的网络课程将通过videoccampus设施向该地区的几个工业场所广播，使许多感兴趣的工程师和管理人员可以在他们的场所学习这些课程。PI计划每周组织一次研讨会，讨论网络研究中的各种主题，届时将由学生、教师以及工业界和学术界的特邀演讲者发表演讲。

Broadband networks are being designed to transport diverse traffic streams with various quality-of-service (QoS) requirements. Accurate characterization of these streams is essential to devising efficient resource allocation strategies that guarantee acceptable QoS without underutilizing network capacity. This project is focused on characterizing compressed video traffic and investigating resource allocation schemes for transporting video traffic over computer networks. New traffic models for VBR video streams will be developed under three strongly related compression algorithms: JPEG, MPEG-1, and MPEG-2. The modeling methodology will be based on the class of M/G/infinity processes, whose versatility will be exploited to capture various forms of traffic correlations. Video sources (single and aggregated) will be characterized at both an entry node and after being multiplexed with other streams (i.e., the departure traffic from a multiplexer). Models for the various layers in hierarchically encoded MPEG-2 video will be developed. The multiplexing performance under video models will be investigated. Corresponding resource allocation strategies for transporting video traffic over broadband networks will be developed. The impact of correlations persistence on the queueing performance under video traffic will be investigated. Several priority scheduling strategies at a multiplexer that is fed by several MPEG-2 input streams will be studied. In connection with the proposed research program, several educational goals will be pursued. New courses on broadband multimedia networks which integrate in their curricula several aspects of the PI's research agenda will be developed. The pedagogical approach in these courses will be a balanced mix of theory and practice and will combine classroom instruction with research-oriented semester projects, hence exposing students (graduate and senior undergraduate) to the intriguing realm of research. Team work will be strongly encouraged in course projects, as it prepares students to future work environments in industry. In an effort to outreach to industry, networking courses taught by the PI will be broadcast over the VideoCampus facility to several industrial sites in the area, allowing many interested engineers and managers to take these courses on their premises. The PI plans to organize a weekly seminar on various topics in networks research, which will feature presentations given by students, faculty, and invited speakers from industry and academia.