Lectures Top-Down Network Design - Chapter 9: Developing Network Management Strategies

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1. Top-Down Network Design Chapter Nine Developing Network Management Strategies Copyright 2010 Cisco Press & Priscilla Oppenheimer
2. Network Management • Helps an organization achieve availability, performance, and security goals • Helps an organization measure how well design goals are being met and adjust network parameters if they are not being met • Facilitates scalability – Helps an organization analyze current network behavior, apply upgrades appropriately, and troubleshoot any problems with upgrades
3. Network Management Design • Consider scalability, traffic patterns, data formats, cost/benefit tradeoffs • Determine which resources should be monitored • Determine metrics for measuring performance • Determine which and how much data to collect
4. Proactive Network Management • Plan to check the health of the network during normal operation, not just when there are problems • Recognize potential problems as they develop • Optimize performance • Plan upgrades appropriately
5. Network Management Processes According to the ISO • Fault management • Configuration management • Accounting management • Performance management • Security management
6. Fault Management • Detect, isolate, diagnose, and correct problems • Report status to end users and managers • Track trends related to problems
7. Configuration Management • Keep track of network devices and their configurations • Maintain an inventory of network assets • Log versions of operating systems and applications
8. Accounting Management • Keep track of network usage by departments or individuals • Facilitate usage-based billing • Find abusers who use more resources than they should
9. Performance Management • Monitor end-to-end performance • Also monitor component performance (individual links and devices) • Test reachability • Measure response times • Measure traffic flow and volume • Record route changes
10. Security Management • Maintain and distribute user names and passwords • Generate, distribute, and store encryption keys • Analyze router, switch, and server configurations for compliance with security policies and procedures • Collect, store, and examine security audit logs
11. Network Management Components • A managed device is a network node that collects and stores management information • An agent is network-management software that resides in a managed device • A network-management system (NMS) runs applications to display management data, monitor and control managed devices, and communicate with agents
12. Network Management Architecture NMS Agent Agent Agent Management Management Management Database Database Database Managed Devices
13. Architecture Concerns • In-band versus out-of-band monitoring – In-band is easier to develop, but results in management data being impacted by network problems • Centralized versus distributed monitoring – Centralized management is simpler to develop and maintain, but may require huge amounts of information to travel back to a centralized network operations center (NOC)
14. Simple Network Management Protocol (SNMP) • Most popular network management protocol • SNMPv3 should gradually supplant versions 1 and 2 because it offers better authentication • SNMP works with Management Information Bases (MIBs)
15. Remote Monitoring (RMON) • Developed by the IETF in the early 1990s to address shortcomings in standard MIBs – Provides information on data link and physical layer parameters – Nine groups of data for Ethernet – The statistics group tracks packets, octets, packet-size distribution, broadcasts, collisions, dropped packets, fragments, CRC and alignment errors, jabbers, and undersized and oversized packets
16. Cisco Tools • Cisco Discovery Protocol – With the show cdp neighbors detail command, you can display detailed information about neighboring routers and switches, including which protocols are enabled, network addresses for enabled protocols, the number and types of interfaces, the type of platform and its capabilities, and the version of Cisco IOS Software running on the neighbor. • NetFlow Accounting – An integral part of Cisco IOS Software that collects and measures data as it enters router or switch interfaces
17. Summary • Determine which resources to monitor, which data about these resources to collect, and how to interpret that data • Develop processes that address performance, fault, configuration, security, and accounting management • Develop a network management architecture • Select management protocols and tools
18. Review Questions • Why is network management design important? • Define the five types of network management processes according to the ISO. • What are some advantages and disadvantages of using in-band network management versus out-of-band network management? • What are some advantages and disadvantages of using centralized network management versus distributed network management?