Snmp C; Snmp Overview - 3Com 4210 PWR Configuration Manual

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SNMP Overview

SNMP Operation
Mechanism
SNMP Versions

SNMP C

ONFIGURATION
The simple network management protocol (SNMP) is used for ensuring the
transmission of the management information between any two network nodes. In
this way, network administrators can easily retrieve and modify the information
about any node on the network. In the meantime, they can locate faults promptly
and implement the fault diagnosis, capacity planning and report generating.
As SNMP adopts the polling mechanism and provides basic function set, it is
suitable for small-sized networks with fast-speed and low-cost. SNMP is based on
user datagram protocol (UDP) and is thus widely supported by many products.
SNMP is implemented by two components, namely, network management station
(NMS) and agent.
An NMS can be a workstation running client program. At present, the
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commonly used network management platforms include Sun NetManager and
IBM NetView.
Agent is server-side software running on network devices (such as switches).
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An NMS can send GetRequest, GetNextRequest and SetRequest messages to the
agents. Upon receiving the requests from the NMS, an agent performs Read or
Write operation on the managed object (MIB, Management Information Base)
according to the message types, generates the corresponding Response packets
and returns them to the NMS.
When a network device operates improperly or changes to other state, the agent
on it can also send trap messages on its own initiative to the NMS to report the
events.
Currently, SNMP agent on a switch supports SNMPv3, and is compatible with
SNMPv1 and SNMPv2c.
SNMPv3 adopts user name and password authentication.
SNMPv1 and SNMPv2c adopt community name authentication. The SNMP packets
containing invalid community names are discarded. SNMP community name is
used to define the relationship between SNMP NMS and SNMP agent. Community
name functions as password. It can limit accesses made by SNMP NMS to SNMP
agent. You can perform the following community name-related configuration.
Specifying MIB view that a community can access.
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Set the permission for a community to access an MIB object to be read-only or
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read-write. Communities with read-only permissions can only query the switch