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

宽带网络正在被设计为传输具有各种服务质量(Qos)要求的不同业务流。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，该策略在不充分利用网络容量的情况下保证可接受的服务质量。该项目致力于描述压缩视频流量的特征，并研究用于在计算机网络上传输视频流量的资源分配方案。VBR视频流的新业务模型将在三种高度相关的压缩算法下开发：JPEG、MPEG1和MPEG2。建模方法将基于M/G/infinity过程的类别，其多功能性将被用来捕获各种形式的流量关联。视频源(单个和聚集的)将在入口节点处以及在与其他流(即，来自多路复用器的出发业务)多路复用之后被表征。将开发用于分层编码的MPEG-2视频中的各个层的模型。对视频模型下的多路复用性能进行了研究。将制定在宽带网络上传输视频业务的相应资源分配策略。研究了视频业务下相关性持久化对排队性能的影响。将研究由多个MPEG-2输入流馈送的多路复用器上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。将开发关于宽带多媒体网络的新课程，在其课程中纳入国际和平研究所研究议程的几个方面。这些课程的教学方法将是理论和实践的平衡结合，并将课堂教学与以研究为导向的学期项目相结合，从而使学生(研究生和高年级本科生)接触到有趣的研究领域。在课程项目中将强烈鼓励团队合作，因为这将为学生适应未来的行业工作环境做好准备。为了扩大与业界的联系，PI教授的网络课程将通过视频校园设施广播到该地区的几个工业现场，使许多感兴趣的工程师和管理人员可以在他们的办公场所学习这些课程。PI计划每周组织一次关于网络研究中各种主题的研讨会，届时将有学生、教职员工以及来自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.