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Telecommunications Management 273-436/635. Network Management. Need for Network Management. Networks and distributed systems are becoming pervasive Networks and distributed applications are critical to organizational performance
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Telecommunications Management273-436/635 Network Management
Need for Network Management • Networks and distributed systems are becoming pervasive • Networks and distributed applications are critical to organizational performance • More things can go wrong in a network environment to disable the network or downgrade performance • Human effort alone is not sufficient to manage complex networks • Automated network management tools are essential Grant
Key areas of Network Management (OSI) • Fault management • Accounting management • Configuration and name management • Performance management • Security management Grant
Fault management The facilities that enable the detection, isolation, and correction of abnormal operation of the OSI environment • Fault: an abnormal condition tha t requires management attention to repair • When faults occur: • Determine where the fault is • Isolate rest of the network from the failure so it can continue functioning without interruption • Reconfigure or modify network • Repair or replace failed components Grant
Fault management • User Requirements • Fast and reliable problem resolution • Immediate notification that a problem has occurred • Information on network status and scheduled and unscheduled service disruptions • Entails: • Proactive, rapid and reliable fault detection and diagnosis • Redundant capacity to provide alternatives • Problem tracking and control Grant
Accounting management • Tracking network use for • cost accounting • abuse of access privileges • Network use efficiency • Planning network growth • User requirements • specifying the kinds of information to be recorded at each node and when they should be sent to higher-level management nodes • Specifying the algorithms to be used in calculating charges • Determining and monitoring access privileges to accounting information Grant
Configuration and name management • Concerned with • initializing a network and gracefully shutting down all or part of it. • maintaining, adding, updating the relationships among components • User requirements • automated startup or shutdown of network operations • identification of network components and desired connectivity level • Ability to change and reconfigure networks in response to new needs and performance evaluation Grant
Performance management • Network communications need to take place within certain performance limits • Performance management: • Monitoring • Controlling • Performance issues • Level of capacity utilization • Nature of network traffic: excessive or not • Level of throughput • Existence of bottlenecks • Response time Grant
Performance management • User requirements • Network performance history (response times and reliability • Network performance statistics to assist in planning, managing and maintaining large networks • Statistics help managers to: • recognize potential bottlenecks • take corrective action such as changing routing tables to balance or redistribute traffic load Grant
Security management • Concerned with • Generating, distributing, and storing encryption keys • Maintaining and distributing password and access control information • Monitoring and controlling access to computer networks • Collecting, storing, examining audit records and security logs • User requirements • Security of information • Security and integrity of network facilities Grant
Network management systems • An integrated collection of tools for network monitoring and control, which contains a • Single, user-friendly operator interface • Minimal amount of separate equipment • Consists of incremental hardware and software implemented on existing network components • Software resides on host computer • Views the entire network as a unified architecture Grant
Network management entity (NME) • Software at each node that perform network management tasks • Tasks performed include • Collection of statistics on communications and network-related activities • Local storage of statistics • Response to commands from the network control center • Sending messages to the network control center when local conditions change significantly Grant
Network management application (NMA) • Collection of software that controls network management activity throughout the network • Includes an operator interface to allow an authorized user to manage the network • Responds to user commands and issues commands to NMEs throughout the network • Uses the same communication architecture as other distributed applications Grant
Agents • End systems that support user applications • host computers • servers • workstations • Nodes that provide a communications service • front-end processors • cluster controllers • bridges • routers Grant
SNA network management architecture • Problem management • problem determination, problem diagnosis, problem bypass and recovery, problem resolution, problem tracking and control • Performance and accounting management • response-time monitoring, availability monitoring, utilization monitoring, component delay monitoring, performance tuning, performance tracking and control, accounting Grant
SNA network management architecture • Configuration management • physical/logical resource identification, resource relationship identification • Change management • software change control, microcode change control, hardware change control Grant
Technical control • Availability - most important characteristic of a network and its services • Increasing reliance on networks make downtime costly • Network technical control involves • Automatic and remote systems testing and monitoring to reduce downtime • Restoring and reconfiguring the system when it fails • Providing network performance and functioning statistics to facilitate Grant
Technical control approaches • Component-level technical control • monitors network activity at the point of attachment of host systems to the network • Line monitors • digital • analog • Protocol analyzers Grant