计算机网络第六版第9章答案,计算机网络第九章答案.doc

计算机网络第九章答案.doc

Chapter 9 Review Questions

A network manager would like to have network management capabilities when (a) a component of the network fails, (b) a component of the network is about to fail, and is acting “flaky” (c) a component of the network has been compromised from a security standpoint and is attacking the network, e.g., by launching a DOS attack by flooding the network with packets, (d) traffic levels exceed a certain threshold on a link, causing packets to be dropped, (e) everything is running smoothly (in order to know that everything is running smoothly and there are no problems). There are many additional reasons as well.

Performance management, fault management, configuration management, accounting management, security management.

Network management is more narrowly defined, as it focuses on the resources in the network – monitoring their functions and controlling their operation. These resources are combined (used) in various ways to implement services. Note that while the network resources may all be functioning as they should, they may not be sufficient to implement a service with a given level of performance; this latter concern is an aspect of service management.

Managing entity: control the collection, processing, analysis, display of network management information, and is used by the network manager to control the devices in the network.Managed device: a piece of network equipment that is under the control of the managing entity.Management agent: a software process running on a managed device that communicated with the managing entity and takes action on the managed device under the control of the managing entity.MIB: pieces of information associated with all of the managed objects in a device.Network management protocol: runs between the managing entity of the management agents on the managed devices, allowing the agents to alert the managing entity to potential problems, and allowing the managing entity to send commands to the management agen