3Com 3CR17660-91, Configuration Manual

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SNMP C
ONFIGURATION
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 other products.
SNMP Operation
Mechanism
SNMP can be divided into two parts, namely, Network Management Station and
Agent:
Network management station (NMS) is the workstation for running the client
program. At present, the commonly used NM platforms include Quidview, 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 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.
■
Define MIB view of subsets of all MIB objects which a community can access.
■
Set read-only or read-write right to access MIB objects for the community. The
read-only community can only query device information while the read-write
community can configure the device.