Business data communications 4e chapter 19

Chapter 19: Network Management Business Data Communications, 4e Network Management Requirements  Fault Management  Accounting Management  Configuration and Name Management  Performance Management  Security Management Business Data Communic ations, 4e Fault Management  A fault is an abnormal condition that requires management attention (or action) to repair  Fault is usually indicated by failure to operate correctly or by excessive errors  Users expect quick and reliable resolution Business Data Communic ations, 4e Responding to Faults  When faults occur, it is critical to quickly:  Determine exactly where the fault is  Isolate the rest of the network from the failure so that it can continue to function without interference  Reconfigure or modify the network to minimize the effect of removing the failed component(s)  Repair or replace the failed components to restore the network to its initial state Business Data Communic ations, 4e Accounting Management  Reasons for accounting management:  Internal chargebacks on network use  User(s) may be abusing access privileges and burdening the network at the expense of other users  Users may be making inefficient use of the network, and the network  The network manager is in a better position to plan for network growth if user activity is known in sufficient detail Business Data Communic ations, 4e Configuration Management  Concerned with:  initializing a network and grace-fully shutting down part or all of the network  maintaining, adding, and updating the relationships among components and the status of components themselves during network operation Business Data Communic ations, 4e Performance Management  Issues of concern to the network manager include:  What is the level of capacity utilization?  Is there excessive traffic?  Has throughput been reduced to unacceptable levels?  Are there bottlenecks?  Is response time increasing?  Network managers need performance statistics to help them plan, manage, and maintain large networks Business Data Communic ations, 4e Security Management  Concerned with  generating, distributing, and storing encryption keys  monitoring and controlling access to networks  access to all or part of the network management information  collection, storage, and examination of audit records and security logs Business Data Communic ations, 4e Network Management Systems  Collection of tools for network monitoring and control, integrated in these ways:  A single user-friendly operator interface for performing most or all network management tasks  A minimal amount of separate equipment  consists of incremental hardware and software additions implemented among existing network components Business Data Communic ations, 4e Network Management System Architecture Business Data Communic 10 ations, 4e Configuration Management  Physical/logical resource identification  Resource relationship identification Business Data Communic 17 ations, 4e Performance & Accounting Management  Response-time monitoring  Availability monitoring  Utilization monitoring  Component delay monitoring  Performance tuning  Performance tracking and control  Accounting Business Data Communic 18 ations, 4e NetView Software  Control facility  Status monitor  Provides the capability to operate the network  Hardware monitor  collects notifications of failures or significant events  Session monitor  Collects session-related information on logical components of the network; includes measurements of data on response time, session failure  Displays status information; reactivates network resources following failures  Help facilities  Descriptions of fields on displays, and a systematic problem-solving facility  Customization facilities:  Permits a user to tailor NetView Business Data Communic 19 ations, 4e Technical Control  Automatic and remote testing and monitoring of the system, to reduce downtime due to the need to locate service personnel  Restoring and/or reconfiguring the system upon failure in real time  Providing network performance and functioning statistics to facilitate planning and management for high availability Business Data Communic 20 ations, 4e Component-Level Technical Control  Line Monitors  Captures the signal between a host system and the network  Generally employed only on the network end  Protocol Analyzers  Can also simulate various network components  Can test communication protocols and codes  Typically handles up to layer of the OSI architecture Business Data Communic 21 ations, 4e Network Technical Control Systems  Integrate control devices and centralize the control of the network Business Data Communic 22 ations, 4e Performance Monitoring  After availability, the second most important characteristic of a network is performance  Performance data must be available in sufficient detail to be able to assess the bottleneck that is causing the problem and to plan appropriate remedial action Business Data Communic 23 ations, 4e Component-Level Monitoring  Response-time monitors  Measures, displays, and records response time of each transaction and the average response time  Hardware monitors  Events: Number of occurrences of specific events  Timing: Timing the duration of a specific signal  Software monitors  Gathers and reports statistics on hardware and systems and applications software activity Business Data Communic 24 ations, 4e Network Monitoring Systems Business Data Communic 25 ations, 4e Indicators Reported by Network Monitors  Service Parameters  Availability  Response Time  Accuracy and Integrity  Efficiency Parameters  Througput  Polling  Utilization Business Data Communic 26 ations, 4e Simple Network Management Protocol (SNMP)  Network Management Model  Management station  Management agent  Management information base  Network management protocol Business Data Communic 27 ations, 4e Role of SNMP Business Data Communic 28 ations, 4e Protocol Specification  Transmission of a message  Receipt of a message  Variable bindings Business Data Communic 29 ations, 4e SNMPv2  Released in 1992, revised in 1996  Addressed functional deficiencies in SNMP  Accommodates decentralized network management  Improves efficiency of data transfer Business Data Communic 30 ations, 4e SNMPv3  Released in 1998, addressed security deficiencies in SNMP and SNMPv2  Does not provide a complete SNMP capability; defines an overall SNMP architecture and a set of security capabilities for use with SNMPv2  Provides three important services: authentication, privacy, and access control Business Data Communic 31 ations, 4e ... Business Data Communic 27 ations, 4e Role of SNMP Business Data Communic 28 ations, 4e Protocol Specification  Transmission of a message  Receipt of a message  Variable bindings Business Data. .. architecture Business Data Communic 21 ations, 4e Network Technical Control Systems  Integrate control devices and centralize the control of the network Business Data Communic 22 ations, 4e Performance... and systems and applications software activity Business Data Communic 24 ations, 4e Network Monitoring Systems Business Data Communic 25 ations, 4e Indicators Reported by Network Monitors  Service