【作者】 范少春；

【导师】 江建军；

【作者基本信息】 华中科技大学 ， 微电子学与固体电子学， 2006， 博士

【摘要】 网络实验系统研究是实验教学和网络教学研究的热点课题之一。各种网络实验系统模型和实例层出不穷,多种新技术也在此得到充分应用,这些研究为网络实验系统发展做出了重要贡献。体系标准化和高效并行性依然是网络实验系统研究的重点和难点,一直以来得到国内外学者的极大重视并被广泛研究。本文从理论和实验两个方面对网络实验系统的体系结构和高效并行性进行了深入的研究。研究的主要创新和结论可概括为以下几个方面。结合网络实验系统研究的意义和现状,分类综述了当前网络实验系统研究方向和技术实现手段。对网络实验系统拓扑结构进行了分析,使用OSI分层原则,提出了分布式网络并行实验系统体系结构及其层次化模型,自下而上依次为物理驱动层、实验操作层、实验网络层、实验数据传输层、实验控制层、决策层和实验应用层。层次化体系结构是网络实验系统研究的基础,对网络实验系统标准化具有积极指导性意义。讨论了物理子层的典型总线和驱动子层的四个实现过程,明确了网络实验系统的基本物理接口。对实验性质进行了研究,从宏观角度讨论了实验系统及其分类特征,分析了实验操作层的三个基本函数,重点讨论了实验控制层的标准实验控制模型和通用服务模型,得出了实验操作层与实验控制层的划分原则及划分的边界条件和最优公式,从而提供了提高实验自身并行效率的方法。以当前标准网络模型为基础,分析了实验网络层的网络数据传输过程。研究了网络数据的标准化传输方式,归纳出了三类结点的网络并行服务模型。通过实验计算分析提出了实验数据传输层的数据标准化理论和方法,分析了用于保障数据传输安全性的数据加密算法。对常用的数据压缩算法RLE、Huffman、LZW在网络实验数据压缩中的应用进行了分析比较,得出不同数据模式下各种算法的选择方法。在已有决策理论的基础上,结合网络实验系统的实际背景,采用层次分析法,从网络实验路由和实验相关性两个方面进行了理论推导,得到了高效并行性的决策理论公式。研究了用于实际应用的动态决策模型。从服务安全性、系统易用性和系统稳定性三个方面讨论了实验应用层的基本功能。研究了嵌入式在线语音、视频以及适用于低带宽的动态热区图像压缩在网络实验系统中的应用方法。使用队列理论对网络实验系统各种服务模型进行了性能评估。分析了基于超市模型的分布式并行网络实验系统实例,采用Poisson流仿真算法,对系统性能进行了评估计算。从服务成本和等待成本两个方面,得出了系统配置优化策略。研究结果表明,基于层次体系结构的网络实验系统具有灵活的分布性能,采用层次划分方法和决策算法后,系统获得了高效并行性能。更多还原

【Abstract】 The research of Network Experiment System is a hot topic in Experiment teaching and network teaching. Various modules and instances had been taken out, and many new technologies had been applied in these systems, which makes great contribution to the development of Network Experiment System. Construction standardization and high efficient parallelism are still the key points of the research, which attracts scholars’great attentions and they do lots of research works on it. In this paper, construction standardization and high efficient parallelism have been discussed deeply from the theoretical and experiment aspects. The main innovation and conclusion could be summarized as followed.Based on the current situation and significance of Network Experiment System research, the researching orientation and technical realization have been classified. The topological structure has been analyzed. As a result, the distributed network parallel experiment system architecture and the hierarchy module based on OSI principle are presented. From the bottom to the top, there are Physical Driver Layer, Experiment Operation Layer, Experiment Network Layer, Experiment Data transport Layer, Experiment Control Layer, Decision Maker Layer and Experiment Application Layer. The hierarchy architecture is the foundation of Network Experiment System research, and plays a guiding role in its standardization.The representative Bus of Physical Layer and four realizations of Driver Layer have been discussed, which defined the basic physical interfaces of Network Experiment System. The character of the experiment has been researched. The experiment system and its classified character have been discussed in a systematic perspective. The three basic functions of Experiment operation Layer have been analyzed. The standard of Experiment Control Layer, the experiment control module and general service module have been discussed in detail. The division principle, the boundary conditions and the optimal formula for Experiment Operation Layer and Experiment Control Layer have been worked out. So the method of improving the parallel execution efficiency of the experiment is provided. Based on the current standard network module, the data transfer in Experiment Network Layer has been analyzed. The standard data transferring mode has been researched and the parallel service module for three nodes has also been concluded. The data standardization theory and the method of Experiment Data Transport Layer have been presented by a real experiment. The encryption algorithm for data transfer security has also been analyzed. General compression algorithms such as RLE, Huffman and LZW have been compared from the perspective of network Experiment data compression, and the choosing method of algorithms corresponding with different modes has been found out.Based on the decision-making theory, the theory calculation has been taken with analytic hierarchy process method, combined with the application background of Network Experiment System. The main theory calculation is implementad from the two aspects of network Experiment routing protocol and Experiment relativity. As a result, the decision theory formula has been worked out for high efficient parallelism. A dynamic decision module for actual application has been researched. The basic function of Experiment Application Layer has been discussed from three aspects of the service security, system usability and system stability. The applied method of the online-embedded voice, video and dynamic thermal region image compression which afford narrow bandwidth area in Network Experiment System have also been researched.The queue theory has been employed for evaluating the performance of various service modes of the Network Experiment System. The distributed parallel Network Experiment System instance based on the supermarket mode has been analyzed. The research adopts Poisson Flow simulation algorithm to evaluate the system performance, and achieve optimization strategy for the system configuration through calculating the service cost and waiting cost. The research result shows that, the Network Experiment System based on hierarchical architecture has flexible distributed property and the system get higher efficient parallelism by adopting the layer division method and decision maker theory.更多还原