IP网络的QOS测量和QOE测量

【作者】 何智星；

【导师】 汪文勇；

【作者基本信息】 电子科技大学 ， 软件工程， 2008， 硕士

【摘要】 随着Internet技术和网络业务的快速发展,网络的规模和复杂性不断增加,新型的网络应用不断涌现,例如VoIP,VOD、网络视频会议等,而这些新型的网络应用的一个共同的需求就是对网络提出质量要求。服务提供商(Internet ServiceProvider)和网络用户都想了解自己提供或正在使用的网络的性能,他们希望得到准确的数字指标来保证网络的性能。如何得到准确、可靠的测量数据以及如何在这些测量数据基础上,对网络的运行状态做一个恰当的评估,从而发现问题,进而提高网络的性能,这是亟待解决的问题。IP网络QoS/QoE测量通过测量获取网络的性能参数,并据此确定网络的问题所在,进一步解决问题使性能得到优化,从而达到人们对网络性能的要求。本文主要是对IP网络的QoS/QoE测量进行了研究。首先,对IP网络的QoS/QoE测量的发展背景和目前网络存在的一些问题以及如何解决这些问题进行了分析;然后详细而系统地讲解了现有的IP网络QoS/QoE测量的参数体系和测量方法。接下来对IP QoS测量中的若干关键技术进行了研究,对IP QoS的重要测量参数如网络时延、丢包率、带宽的测量作了侧重的讲解,并提出了对这些参数测量结果的分析模型。另外,本文的课题是面向性能管理过程中的突出问题,在三大基本网络性能指标(时延、丢包率和带宽)的基础上,探索和研究了能够直接表达网络运行QoS的指标体系。为了尽量准确表达网络运行的健康程度,本文提出了一种新的指标体系,这种指标体系有别与传统的若干平行指标,是一种层次化的立体结构,包括从网络层面到应用层面的不同指标。并针对所提出的指标体系,提出相应的被动测量方法,通过监听和分析骨干网络关键路径中的流量,来分析IP网络各种端到端会话的分组序列、传输质量,从而进一步得出IP子网与子网之间的各项QoS指标。与现有测量方式相比,本文提出的方法能够更加准确快速地对IP网络的QoS/QoE质量进行测量。更多还原

【Abstract】 With the rapid development of the Internet technologies and the IP network applications, the scale and the complexity of IP network expands continuously, and new network applications appear continuously such as VOIP, VOD, network video conference and so on, in consequently these new applications all need a higher qualification of service. Internet Service Provider (ISP) and the very important client of network want to know the performance of the supported network by them or network in use, and they hope to get the exact data to guarantee the performance of network. So how to get exact and reliable testing data and how to make a right evaluation for the whole network’s running status based on the large number probing data, and then find the question, thereby improve the performance of the network, this is a question desiderate to be solved. The IP network QoS/QoE measurement can get the performance parameter of the given network in use according to the measurement of network, and then find out the problems of the network, and optimize the performance of the given network accordingly to achieve the demand of network users.This paper mainly has studied the IP network QoS / QoE measurements. First, it has analyzed the the background of development and some current problems about IP network QoS / QoE measurements and how to solve these problems, and then it expounded systematically the existing IP network QoS/QoE measurement system and stucture of the parameters of measurement. Second, it has researched various key technologies of IP network QoS/QoE measurements. It focused on the some important IP QoS measurement parameters such as network delay, packet loss, bandwidth, and made the analysis model of these parameters on the network measurements.In addition, the subject in this paper with the outstanding problems in the network management process is explored and researched the QoS indicators that could directly express network operating system on the basis of three network performance indicators (network delay, packet loss and bandwidth). As accurately as possible to express the healthy operation of the network level, this paper presents a new network performance indicators system that has a number of different network performance indicators from the traditional indicators, and this indicator system is a level of three-dimensional structure, including various indicators from the network level to the network application level. And on the proposed network performance indicator system, it proposed the passive measurement method that through the backbone network monitoring and analysis of the critical path of traffic, to analyze the packet sequence and transmission quality of the IP network end-to-end conversation and conclude the QoS indicators among the sub-networks. Compared with the existing measurement methods, the method proposed in this paper can be more quickly and accurately on the IP network QoS / QoE measurement.更多还原