Internet环境下的资源管理模型及算法研究

发布时间：2018-04-15 00:08

本文选题：网格 + 对等网络　；参考：《山东师范大学》2009年博士论文

【摘要】： 网络管理理论与技术是管理科学与工程的一个重要研究领域,随着互联网技术日益成熟,网络资源越来越丰富,从管理科学角度研究如何有效地进行网络资源管理、提高网络资源利用率具有重要意义,因此新一代网络应用平台和网络管理理论及关键技术是目前网络管理技术的一个重要研究方向。迄今为止,现存的技术主要为资源集中管理提供了有效的管理方法,但很多情况下资源都分布存放在不同地点,需要实施分布管理的方法和技术。例如,考虑我国中小学教育资源共享问题,目前各个学校拥有丰富的教学资源,包括各学科教学课件、优秀教学案例、实验案例、精品课程的教学录像以及各类教学管理软件等,如何利用网络资源管理技术高效的共享这些资源,避免盲目重复开发,是迫切需要研究的问题。因此,研究基于分布式资源管理的网络体系结构,开发标准的网络资源管理平台具有重要意义。作为一个典型应用,可以利用该平台实现中小学教育资源的分布管理,为我国基础教育资源管理提供一个通用开放的软件支撑平台,对于加强各地中小学之间的交流与合作,提高整体教学水平具有重要作用。目前,不同机构的资源一般都集中存储在各自的服务器上,以Web方式供用户访问。这种集中式资源管理具有很高的效率,但是Web服务器瓶颈问题、资源副本管理问题、资源发现问题和网络带宽问题等若干因素给这种应用模式带来很大的挑战,诸多技术问题亟待解决。网格作为一种日益流行的网络计算平台,为网络资源管理提供了一种有效的解决方案。在不改变现有资源存储模式的前提下,建立一个分布式资源管理平台来整合这些资源,需要研究网络环境下分布式资源管理的网络体系结构、资源管理机制和服务理论。论文以我国中小学教育资源管理为应用背景,重点研究了网络环境下进行资源共享的系统拓扑结构、资源发现机制、资源感知模型及资源副本管理技术等,为建立互联网络环境下网格资源管理平台探索有效的方法和途径。论文主要研究内容及创新工作包括: 1.研究了资源共享系统的拓扑结构,以网络节点处理能力和物理网络参数为依据构建了RP(k)C-Grid系统,设计了高效的消息路由算法MR-RP(k),解决了现有拓扑结构的系统瓶颈、可扩展性差及拓扑失配问题。目前网络资源管理系统主要有集中式、分布式非结构化和分布式结构化等结构形式。这些结构各有其不足:集中式结构的服务器是系统瓶颈;分布式非结构化网络基于泛洪的查询机制容易造成网络拥塞,系统可扩展性差;分布式结构化网络目前主要采用DHT机制组织网络节点和资源,这种方式使得物理上相邻的节点经过哈希算法处理后逻辑上可能相距很远,降低了网络的运行效率。分布式结构化网络的DHT路由策略、节点的动态离开与加入给系统带来的震荡也是需要深入研究的问题。由于RP(k)结构充分利用了Petersen的稳定性和环的简单性,具有短的网络直径、简单的拓扑结构及高效的路由策略,基于RP(k)构建的RP(k)C-Grid系统和其它拓扑结构相比具有更好的稳定性和更高的通信效率。 2.针对资源搜索问题,设计了RP(k)C-Grid上的PFS资源发现算法,提出了查询登记机制避免重复泛洪。和其它搜索算法相比,PFS算法有效降低了资源搜索延迟时间,减少了查询消息跳数,在系统规模增大时有更高的搜索效率。目前资源搜索方法主要有集中式方法和分布式方法,集中式资源搜索效率较高,但可扩展性差,存在单一故障点;基于DHT的分布式系统资源定位方法可伸缩性好,但分布式哈希表的拓扑失配问题降低了系统的资源搜索效率。PFS搜索算法充分利用了RP(k)C-Grid系统的结构特点,有效发挥簇头节点的性能优势,采取簇头探察、簇头泛洪和RP(k)C轮询相结合的方法减少泛洪次数。查询登记机制使得对同一资源的重复查询请求可以在簇头节点进行高效处理而避免重复泛洪。 3.为提高簇头节点的资源感知能力,设计了资源目录全局广告算法,使得簇头节点能够快速获取全局资源目录视图,以良好的资源感知能力实现对资源搜索的快速响应。资源需求者对共享资源信息的感知能力是影响资源发现效率的重要因素。广告使得供应商以最快捷的方式把商品介绍给用户,用户也以最小的搜索代价从广告中获取满意的商品信息。基于这种市场模式的启发,建立了资源目录广告模型,设计了RP(k)C上的资源目录全局广告算法RP(k)C-DA,该算法分两部分实现:Petersen内目录广告和RP(k)C目录广告。针对不同系统规模进行了实验分析,和其它文献的方法进行了比较,验证了资源目录全局广告算法的优势。 4.从提高副本利用率、降低副本维护代价角度入手,提出了基于资源访问热度队列策略的自适应关口副本算法,把访问热度高的资源在其它节点建立副本,均衡访问负载,降低当前资源节点的副本替换频率。资源副本是网络环境下文件资源共享时保证资源可用性和降低访问迟延的有效方式,但是副本如何放置才能达到更高的使用效率而不浪费网络带宽和存储空间,这需要在特定拓扑结构下进行分析。针对RP(k)C-Grid拓扑结构,提出了自适应关口副本机制,对成功跨簇查询的资源文件在簇头节点建立副本以提高查询响应速度。由于频繁的关口副本建立与替换会增加簇头节点的存储代价及性能损耗,提出采用资源访问热度队列策略对副本进行管理维护,实验证明该策略有效改善了系统副本管理性能。 5.以教育资源共享管理为应用背景,利用研究的网络资源管理技术建立了一个教育资源网格系统RP(k)C-Grid,实现了网络环境下的资源管理、副本管理以及资源搜索等。根据都柏林元数据标准和CELTS-42规范提出了一种实用的基础教育资源元数据模型,用来表示教育资源网格中文件资源的元数据信息。目前我国各省市及县区的中小学和各级教育管理部门一般都拥有较高性能的服务器,并积累了大量的教学资源。这些服务器在物理位置的分布上相对规则,适合建立结构化拓扑。利用研究的网络资源管理技术设计了一个教育资源网格应用实例,分析了网格构建的关键技术,给出了系统主要模块设计。RP(k)C-Grid系统的建立和运行方式更适合目前我国中小学教育资源管理现状。本文的研究进一步丰富和完善了网络环境下资源管理技术的模型及算法,为网络环境下资源共享探索有效的方法。
[Abstract]:Network management theory and technology are an important research field of management science and engineering . With the increasingly mature Internet technology and more and more network resources , it is important to study how to effectively carry out network resource management and improve the utilization rate of network resources from the perspective of management science .

At present , the resources of different institutions are generally centrally stored on their respective servers for user access in a Web manner . This centralized resource management has a very high efficiency , but the problems of Web server bottleneck , resource copy management , resource discovery and network bandwidth issue a great challenge . Many technical problems need to be solved . As an increasingly popular network computing platform , a distributed resource management platform is established to integrate these resources , and the network architecture , resource management mechanism and service theory of distributed resource management in the network environment need to be studied .

This paper focuses on the system topological structure , resource discovery mechanism , resource perception model and resource copy management technology of resource sharing under the network environment in order to establish an effective method and approach for the establishment of grid resource management platform in Internet environment . The main research contents and innovations include :

1 . The topological structure of the resource sharing system is studied , and the RP ( k ) C - Grid system is constructed based on the network node processing capability and the physical network parameters . The efficient message routing algorithm MR - RP ( k ) is designed , which solves the problems of system bottleneck , poor scalability and topological mismatch of the existing topology .

At present , the network resource management system is mainly centralized , distributed unstructured and distributed structured and so on . Each of these structures has its disadvantages : the centralized structure of the server is the bottleneck of the system ; the distributed unstructured network can easily cause network congestion and poor system scalability . The DHT routing strategy of the distributed structured network , the dynamic departure of the node and the oscillation caused by adding to the system are also the problems that need to be further researched . As the RP ( k ) structure makes full use of the stability of the network , the simple topology and the efficient routing strategy , the RP ( k ) C - Grid system based on RP ( k ) has better stability and higher communication efficiency .

2 . Aiming at the problem of resource search , the PFS resource discovery algorithm on the RP ( k ) C - Grid is designed , and the query registration mechanism is proposed to avoid repeated flooding . Compared with other search algorithms , the PFS algorithm effectively reduces the delay time of the resource search , reduces the number of query message hops , and has higher search efficiency when the system scale is increased .

The current resource search method mainly includes the centralized method and the distributed method , the centralized resource search efficiency is high , but the expansibility is poor , there is a single failure point , the distributed system resource positioning method based on DHT has good scalability , but the topology mismatch problem of the distributed hash table reduces the resource search efficiency of the system . The PFS search algorithm fully utilizes the structure characteristics of the RP ( k ) C - Grid system , and effectively functions the performance advantage of the cluster head node . The query registration mechanism makes the repeated query request to the same resource effectively processed in the cluster head node to avoid repeated flooding .

3 . To improve the resource awareness of the cluster head node , the global advertisement algorithm of the resource directory is designed , so that the cluster head node can quickly acquire the global resource directory view , and realize the quick response to the resource search with good resource sensing capability .

This paper introduces the resource directory advertisement model and designs the resource directory global advertisement algorithm RP ( k ) C - DA on RP ( k ) C .

4 . Starting from improving the utilization rate of the replica and reducing the cost of the copy maintenance cost , a self - adaptive gateway replica algorithm based on the hot queue strategy of resource access is proposed . A copy of the resource with high access heat is established at other nodes , the load is balanced , and the replacement frequency of a copy of the current resource node is reduced .

A copy of resources is an effective way to ensure resource availability and reduce access delay when file resources are shared in a network environment . However , how to put a copy in order to achieve higher use efficiency without wasting network bandwidth and storage space is required to be analyzed under a specific topology structure . For the RP ( k ) C - Grid topology structure , a copy of the resource file of a successful cross - cluster query is set up to improve the query response speed . Because frequent gateway copy establishment and replacement can increase the storage cost and performance loss of the cluster head node , a copy is managed and maintained by using a resource access hot queue policy , and the experiment proves that the policy effectively improves the system copy management performance .

5 . With the management of educational resources as the application background , an educational resource grid system RP ( k ) C - Grid is established by using the research network resource management technology , and the resource management , copy management and resource search in the network environment are realized .

Based on the Dublin metadata standard and CELTS - 42 specification , a practical metadata model of basic education resources is proposed , which is used to represent the metadata information of file resources in the educational resource grid . At present , the primary and middle schools and all levels of educational administration departments in various provinces , cities and counties of China generally have higher performance servers , and a large number of teaching resources have been accumulated . The key technology of grid construction is analyzed . The key technology of grid construction is analyzed , and the main module design of the system is given . The establishment and operation of the RP ( k ) C - Grid system is more suitable for the present situation of primary and middle school education resources management in China .

The research of this paper further enriches and perfects the model and algorithm of resource management technology in the network environment , and provides an effective method for resource sharing under the network environment .

【学位授予单位】：山东师范大学
【学位级别】：博士
【学位授予年份】：2009
【分类号】：TP393.02

【引证文献】