11.9 Conclusion

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Most network management architectures use the same basic structure and set of relationships. Managed elements, such as computer systems and network devices, run software that enables them to send alerts when they recognize problems; for example, when one or more user-determined thresholds are exceeded. Upon receiving these alerts, management entities are programmed to react by executing one, several, or a group of actions, including operator notification, event logging, system shutdown, and automatic attempts at system repair.

Management entities can poll end stations to check the values of certain variables. Polling can be automatic or user-initiated, but agents in the managed devices respond to all polls. Agents first compile information about the managed devices in which they reside, then store this information in a management database, and finally provide it to management entities within NMSs via a network management protocol such as SNMP.

SNMP’s popularity stems from the fact that it works and is reliable, widely supported, and extendible. The protocol itself is in the public domain. SNMP capabilities have been integrated into just about every conceivable device that is used on today’s LANs and WANs, whether they are wired to the network or linked wirelessly to the network.

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