AN,INTRODUCTION,TO,COMPUTER,NETWORK,MANAGEMENT

最新资料欢迎阅读 AN,INTRODUCTION,TO,COMPUTER,NETWORK,MANAGEMENT Since the 21st century, with the popularization of computer and the development of computer technologies and communications technologies, network has been integrated into daily life more and more extensively, and has become the pillar of today”s information age. Network originates from the combination of computer and communications. The dependence of information society on network has made it very important for the network to be reliable itself, and has raised the bar on its management. to improve network management, and to spread information in a safe and swift manner. The computer network management system has become more and more important. I. Basic knowledge of computer network management system 1. Definition of computer network management systemThe computer network management system is the software system used to manage the network. The computer network management is to gather the static and dynamic operating information of the various parts of the network, to analyze and to process the information, so as to ensure the safe, reliable, efficient running of the network, to distribute the network resources reasonably, to allocate network load dynamically, to optimize the network performance, and to reduce the cost of network maintenance.2. The fundamental components of the network management system1) Network manager. The network manager is the substantial part to implement the network management. Being the core of the network system, he/she stays at the management workstation, performing the various complex tasks related to network management. 2) Management agent. The network management agent is the software module set in the network equipment, including UNIX workstation, network printers, and some other network equipment. It can acquire the information on the operating status of local equipment, its features and system allocation. 3) Management information base (MIB). The management information base is stored at the store of the managed target. As a dynamically refreshed information base, MIB includes the information on network equipment allocation, data communications, security and equipment features. The information delivered dynamically to the MIB, forms the data source of the network management system. 4) Agent server and management protocol. The agent server serves as a bridge between the standard network management software and the system that does not support this standard protocol. With the server, the protocol can be upgraded to the newer version without upgrading the entire network. As for the network management system, it is the network management protocol used by the manager and the agent. 3. Functions of network management systemThe network management system has five big functions: allocation management, performance management, security management, failure management and fee calculation management.These five basic functions are both independent of and related to each other. Among them, failure management is the core of entire network management; allocation management is the basis of all functions because other functions all need to use the information of allocation management; performance management, security management and fee calculation management are relatively more independent, especially fee calculation management because the fee calculation policies are very different for different application units, and the development environments to which fee calculation applies are very different; therefore, fee calculation management is usually developed specific to actual individual conditions .4. Network management protocolDue to the features commonly found in network, such as multi-manufacturer, isomerization and inherent distribution, standard is introduced to network management to standardize manufacture of network equipment and development of network management system. Network management protocol is such a standard. Currently, the Simple Network Management Protocol (SNMP) and the Common Management Information Service (CMIS)/Common Management Information Protocol (CMIP) are the most influential ones. They represent the two big solutions for network management now. Due to its complexity, CMIP is slow to be standardized, and has not been widely accepted, SNMP, on the other hand, has been supported by various manufacturers, and has been widely applied for its practical simplicity. II. The developing trend of computer network management systemComputer network management system is now starting to enter the application layer. Traditionally, computer network management system mainly concerned about the various network equipment, which was in the network layer. Centered around equipment or equipment assemblage, it used SNMP to control and manage equipment. Web users have higher demand on network as well as network bandwidth. Some demands concern the transmission of time sensitive data, such as real-time audio and video, but some data are not time sensitive. Therefore, considering the limit current network bandwidth, it is imperative to change the previous practice of not differentiating service content, but to provide high quality service to all individual users according to the service contents, so as to better utilize the resources of bandwidth. This is called QOS(Quality of Services). With this idea, network management starts to move the controlling force from network layer to application layer. R1MON2 has tried this way, which was an important change to network management system. In spite of all the versatile technologies used in network management system, some trends have developed as is shown below, as a result of standardization activities and the need for system interconnection. 1. Distributed network managementThe key of distributed object is to solve the problem of cross-platform connection and interaction, and to realize distributed application system. The CORBA presented by OMG is quite an ideal platform. Distributed network management is to set up multi domain management processes. Domain management process takes charges of the objects in the domain, and at the same time, different domains coordinates and interacts with each other, so as to perform the management of global area network. Thus, not only is the load of central network management reduced, but time lag for transmission of information on network management is decreased as well, which makes management more effective. Distributed technologies mainly have two aspects: one utilizes CORBA, and the other mobile agent technology. In the near future, centralized distributed network management model can be used to realize the functions of centralization and data acquisition distribution. 2.Integrated network managementIntegrated network management requires network management system provide the multitier management support. It can keep all the sub networks in perspective through one operating platform, understanding its operating businesses, identifying and eliminating failures. Thus, the multi interlinked networks management is fulfilled. With network management having become more and more important, many different network management systems have emerged, including those that manage SDH networks and IP networks. The networks managed by these systems interlinks with and interdependent on with each other. There are multi network management systems at the same time. They are independent, in charge of different parts of the network. There can even be a few network management systems with same contents existing concurrently. They come from