POF-CCN中的实时媒体传输与拥塞控制研究

发布时间：2018-01-01 17:01

本文关键词：POF-CCN中的实时媒体传输与拥塞控制研究　出处：《中国科学技术大学》2016年硕士论文　论文类型：学位论文

【摘要】：内容中心网络CCN以内容为主体,软件定义网络SDN使用控制层对底层网络设备进行统一管理,二者都是未来网络研究的重要方向。华为提出的协议无感知转发POF,进一步提高了SDN的可编程性。据此,我们提出了POF-CCN网络架构。CCN具有多播和网络内缓存的特性,在视频传输方面独具优势。目前CCN中的实时媒体传输方案大多没有考虑实时媒体数据传输的持续性特征,使用一对一的请求模式会造成资源浪费。此外,作为一种新的网络架构,进行拥塞控制研究是非常有必要的。CCN中的拥塞控制大多利用往返延迟进行拥塞判断,但是由于CCN中无连接状态且具有内容多源获取的特征,这种判断并不准确；有的研究通过为每个流维持RTT来提高准确性,但是这种方法开销过大。针对目前CCN中实时媒体传输的问题,本文提出一种区分实时媒体数据和普通数据的传输方案。本文为实时媒体数据传输设计保留前缀的命名规则,并根据命名方案设计转发流程和转发规则。在直播源和用户节点处,利用VLC框架对视频串流,并用开源Libpcap库编写程序,抓取数据包并根据POF-CCN内容转发协议头封装、解封数据,最后通过POF-CCN网络进行数据转发,完成整个实时媒体方案的部署。针对隐式拥塞控制准确度不高的问题,本文设计了一种基于显式反馈的拥塞控制判断方法,网络中的节点根据Interest包队列长度预测拥塞程度,并在兴趣包中标记不同的拥塞值,在预测到网络拥塞时及时将拥塞信息反馈给数据接收端。接收端根据拥塞程度值调节拥塞窗口大小,网络中节点则对网络中的流进行公平带宽分配,并根据预测的拥塞程度值对本节点中的请求队列进行整形。本文提出的区分实时媒体和普通数据的传输方案,在POF-CCN中成功部署,实验表明该方案对减轻网络传输压力,研究内容中心网络区分不同业务的内容传输方案有一定借鉴意义。此外,仿真实验表明,基于显式反馈的联合拥塞控制方案能够起到较好的拥塞调节效果,对研究内容中心网络中新的拥塞控制方法有定参考价值。
[Abstract]:The content of CCN in network center as the main content, software defined network SDN control layer on the underlying network equipment for unified management, the two are the important direction of network research in the future. HUAWEI's non aware forwarding protocol POF, to further improve the programmability of SDN. Accordingly, we put forward the characteristics of the POF-CCN network architecture with.CCN multicast and network cache, the unique advantages in video transmission. The real-time media transmission scheme in CCN are not considered persistent features of real-time media data transmission, using request mode one will cause the waste of resources. In addition, as a new kind of network architecture, research on congestion control and congestion control is it is necessary to use.CCN most of the round-trip delay congestion judgment, but because there is no connection state and has the characteristics of multi-source CCN content acquisition, this judgment is not Do some research; to improve the accuracy by maintaining the RTT for each flow, but this method costs too much. Aimed at the real-time media transmission in CCN, this paper proposes a transmission scheme to distinguish real-time media data and general data. This paper set the naming rules for reserved prefix meter real-time media data transmission, and according to the naming scheme the design of forwarding process and forwarding rules. In the broadcast source and user nodes of video streaming using VLC framework, and write the program with the open source Libpcap library, and according to the POF-CCN content of capture data packet forwarding protocol header package, sealing solution data, finally the data forwarding through the POF-CCN network, complete the real-time media deployment scheme for the accurate. The problem is not high degree of implicit congestion control, this paper designs an explicit feedback congestion control method based on the judgment, the nodes in the network based on Interest packet queue length The prediction of the degree of congestion, and interest in the package mark different value in the prediction of congestion, network congestion timely congestion feedback information to the data receiver. The receiver according to the congestion degree of adjusting the congestion window size, the nodes in the network are fair bandwidth allocation in the network flow, and according to the degree of congestion prediction value through the shaping of the nodes in the request queue. The transmission scheme proposed in this paper to distinguish real-time media and general data, successful deployment in POF-CCN. The experimental results show that the scheme is to reduce the network transmission pressure, has certain reference significance to the content transmission scheme to distinguish between different business research center network. Furthermore, simulation results show that the joint congestion control for the explicit feedback congestion control can play better based on definite reference value for the new congestion control method research center in the network.

【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TP393.06

【相似文献】