Snmp Overview - 3Com 7757 Configuration Manual

SNMP C
ONFIGURATION
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SNMP Overview

By far, the simple network management protocol (SNMP) has gained the most
extensive application in the computer networks. SNMP has been put into use and
widely accepted as an industry standard in practice. It is used for ensuring the
transmission of the management information between any two nodes. In this way,
network administrators can easily search and modify the information on any node
on the network. In the meantime, they can locate faults promptly and implement
the fault diagnosis, capacity planning and report generating.
SNMP adopts the polling mechanism and provides the most basic function set. It is
most applicable to the small-sized, fast-speed and low-cost environment. It only
requires the connectionless transport layer protocol UDP; and is thus widely
supported by many products.
SNMP Operation SNMP can be divided into two parts, namely, Network Management Station and
Mechanism Agent:
Network management station (NMS) is the workstation for running the client
program. At present, the commonly used NM platforms include 3Com's Network
Management Products, Sun NetManager and IBM NetView.
Agent is the server software operated on network devices.
The NMS can send GetRequest, GetNextRequest and SetRequest messages to the
Agent. Upon receiving the requests from the NMS, Agent will perform Read or
Write operation according to the message types, generate and return the
Response message to the NMS.
Agent will send Trap message on its own initiative to the NMS to report the events
whenever the device status changes or the device encounters any abnormalities
such as restarting the device.
SNMP Versions Currently SNMP Agent of the device supports SNMP V3, and is compatible with
SNMP V1 and SNMP V2C.
SNMP V3 adopts user name and password authentication.
SNMP V1 and SNMP V2C adopt community name authentication. The SNMP
packets failing to pass community name authentication are discarded. The
community name is used to define the relation between SNMP NMS and SNMP
Agent. The community name can limit access to SNMP Agent from SNMP NMS,
functioning as a password. You can define the following features related to the
community name.