【作者】 张金祥；

【导师】 吴泉源；

【作者基本信息】 中国人民解放军国防科学技术大学 ， 计算机科学与技术， 2001， 博士

【摘要】 随着网络规模的不断扩大，网络提供服务的日益多样性，传统的网络管理模式和简单的信息访问策略已越来越难以适应用户对网络发展的需求。为了获得一个有分布特性、可伸缩性、支持互操作、管理信息自适应访问的电信网络管理系统，国内外的学者和网络管理系统开发厂商从不同角度、不同的技术层面展开了对分布式网络管理的研究。基于CORBA(Common Object Request Broker Architecture，公共对象请求代理体系)的网络管理技术就是在这一背景下涌现出来的新课题，得到了电信网络技术、OMG(Object Management Group，对象管理组)、网络管理技术和分布对象技术等诸多领域研究人员的共同的广泛关注。 本文的工作围绕基于CORBA技术实现分布式网络管理的各个层面深入展开，主要研究成果有： 1．针对CORBA管理本身不支持对象的定界、过滤和多个对象的访问功能，以及在CORBA管理实用化时，可能导致网管流量急剧增大的不足，基于CORBA管理与OSI系统管理的各自特点，我们提出了一种基于CORBA的多级网络管理体系结构MHNM(Multi-Hierarchy Network Management)，该结构结合了OSI系统管理与CORBA的优点，采用pseudo-Agent分布式管理和被管对象分类预取值Cache技术，提供多对象快速访问的功能支持，解决了CORBA“单个对象访问”造成的网络管理性能下降问题。 2．针对CORBA管理信息的组织采用类似于非结构化的文件方式，及其处理管理信息的查询、插入、删除等操作效率较低的缺陷，在CORBA管理中，提出采用类似于OSI系统管理和SNMP(Simple Network Management Protocol，简单网络管理协议)管理的MIB(Management Information Base，管理信息库)树形组织与存储。所有的被管对象实例存于MIB中，并且它们的视图组成一树形结构，以便于定位和查询。进而，给出了CORBA被管对象的组织策略、定义策略、实现策略和发现策略，实现了CORBA网络管理中被管对象的结构化组织和高效操作。 3．由于电信网络中，TMN(Telecommunications Management Network，电信管理网)网元层被管对象的数目有10~6数量级之多，对被管对象的高效访问策略一直是制约网络管理性能的重要因素。针对传统的定时提取网络管理信息方法的不足，提出了一种提取多管理对象信息的新算法——自适应算法SAA(Self-Adaptive Algorithm)，该算法能在不改变管理协议，如IIOP(Internet Inter-Operability Protocol)、SNMP或CMIP(Common Management Information Protocol，公共管理信息协议)的情况下，采用自适应策略、容错策略、动态识别被管对象状态策略、被管对象存储空间的动态刷新策略，根据本次访问被管国防科学技术大学研究生院学位论文对象所得出的网络通信量，自适应地调整下次应该访问的被管对象和读取被管刘·象数据的时间间隔，从而可以较少地消耗所用的网络带宽和CPU资源。 4.为进一步减少网络管理系统对网络带宽的占用，结合被管对象信息的收集策略直接影响网管系统性能的特点，针对异构大型网络环境下多管理对象的信息收集问题，提出了一种提取多管理对象信息的新算法—组预取算法GPA(Group一Prefetehing Algorithim)，该算法同样能在不改变管理协议，如IIOP、SNMP或CMIP的情况下，采用组预取策略、组对象自适应扩充策略、组对象自适应收缩策略、容错策略等，将多个分散的、处于相同或不同被管设备上的、在未来一段时间内的管理对象的访问组合在一个预取组中进行访问，减少对管理对象的访问频度，从而可以较少占用网络资源，减小整个网络开销。 5.以中国移动通信网本地网网管系统设计为背景，以我们先后开发中国移动通信网本地网网管系统、广电有线电视传输网网管系统和邮政网网管系统的实践为基础，结合多级网络管理体系结构Ml江NM、管理信息的组织策略、提取管理信息的自适应算法SAA和组预取算法GPA，在基于CORBA的分布计算软件平台StarBus上，详细分析了基于CORBA技术实现实用的异构网管系统集成管理的关键技术、途径和软件结构。 文章的最后总结了本文的主要研究成果，并概述了进一步的研究方向。更多还原

【Abstract】 As the expansion of network scale and the service provided by it becomes more complex, the traditional pattern of network management and information retrieval scheme becomes more and more difficult to meet the needs of network users. Thus, the researches on distributed network management have been outspreaded from different aspects to obtain a network management system that is distributed, scalable, operational and information self-adaptive retrieval. In this background, network management technique based-on CORBA(Common Object Request Broker Architecture) appears, which quickly becomes the hotspot in many fields such as OMG(Object Management Group), telecommunications, network management, and distributed object technology etc.This paper fully studies the different aspects of network management technique based-on CORBA, and its main achievements are as follows:1. As CORBA does not provide the function of scope, filtering and multi objects or attributes to access, which will cause too much traffics and violate such principle as that management traffic can not affect more on network performance, Combined with the advantages of CORBA and OSI management, This article has put forward a MHNM (Multi-Hierarchy Network Management) Architecture in the domain of the management of telecommunications network, using pseudo-Agent distributed management and grouping managed objects to cache. It has assured the performance of network management by providing multi object or attributes quick access.2. As the scheme of information arrangement of CORBA is flat file style, which handles querying, deleting, and inserting information inefficiently compared to OSI. A tree structure of managed objects arrangement like MIB(Management Information Base) has been used to provide efficient operation on managed objects. In addition, arrangement, definition, implementation and finding schemes for CORBA managed objects are also given by the tree structure.3. As there are up to 106 managed objects on element level of TMN (Telecommunications Management Network) in telecommunications network, and the scheme to collect management information affects the performance of network management, A new algorithm-SAA (Self-Adaptive Algorithm) used for retrieving multi objects information has been put forward in this thesis. SAA can adjust the retrieving objects and interval of retrieval self-adaptively by using the schemes of self-adaptivity, fault tolerance, recognition status of object dynamically etc., and thus can use fewer network resources without alteration of SNMP(Simple NetworkManagement Protocol), IIOP(Internet Inter-Operability Protocol) or CMIP(Common Management Information Protocol).4.To decrease the usage of network resources by network management systems even more, combined with the fact that the performance of network management is affected by the scheme to collect management information, A new algorithm-GPA (Group-Prefetching Algorithm) has been put forward used for retrieving management information from the element level in heterogeneous WAN (Wide Area Network). GPA can adjust many little retrieving objects into one prefetching group to access by using the schemes of group prefetching, objects of group changed self-adaptively, fault tolerance etc., and thus can decrease the frequency of retrieval, use fewer network resources and decrease the network overhead without alteration of IIOP, SNMP or CMIP too.5.In the background of the design and implementation of network management system for the local network of China Mobile, we have analyzed and designed detailedly the key technique, approach and software architecture of a practical network management system based on StarBus, which use MHNM architecture, the scheme of managed objects arrangement, SAA, GPA and practical skills achieved when we developed China Post and China Broadcast and TV network management systems.In the end, we summarize the main achievement of this paper and state some further work in the future.更多还原