Planet ADN-4000 User Manual page 104

Figure2: An SNMP-Managed Network Consists of Managed Devices, Agents, and NMSs
Managed devices are monitored an d controlled using f our basic SNMP commands: read,
write, trap, and traversal operations.
The read command is used by an NMS to monitor managed devices. The NMS examines
different variables that are maintained by managed devices.
The write command is used by an NMS to control managed devices. The NMS changes
the values of variables stored within managed devices.
The trap command is used by managed devices to asynchronously report events to the
NMS. When certain types of events occur, a managed device sends a trap to the NMS.
Traversal operations are used by the NMS to determine which variables a managed device
supports and to sequentially gather information in variable tables, such as a routing table.
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