1-11 SNMP ConfigurationWhen configuring SNMP, go to these sections for information you are interested in:z SNMP Overviewz Configuring Basic SNMP Functionsz Configuring Trap-Related Functionsz Enabling Logging for Network Managementz Displaying SNMPz SNMP Configuration Example1.1 SNMP OverviewThe Simple Network Management Protocol (SNMP) is used for ensuring the transmission of themanagement information between any two network nodes. In this way, network administrators caneasily retrieve and modify the information about any node on the network. In the meantime, theycan locate faults promptly and implement the fault diagnosis, capacity planning and reportgenerating.As SNMP adopts the polling mechanism and provides basic function set, it is suitable forsmall-sized networks with fast-speed and low-cost. SNMP is based on User Datagram Protocol(UDP) and is thus widely supported by many products.1.1.1 SNMP Operation MechanismSNMP is implemented by two components, namely, network management station (NMS) andagent.z An NMS can be a workstation running client program. At present, the commonly usednetwork management platforms include QuidView, Sun NetManager, IBM NetView, and soon.z Agent is server-side software running on network devices (such as switches).An NMS can send GetRequest, GetNextRequest and SetRequest messages to the agents. Uponreceiving the requests from the NMS, an agent performs Read or Write operation on the managedobject (MIB, Management Information Base) according to the message types, generates thecorresponding Response packets and returns them to the NMS.When a network device operates improperly or changes to other state, the agent on it can alsosend traps on its own initiative to the NMS to report the events.1.1.2 SNMP VersionsCurrently, SNMP agent on a switch supports SNMPv3, and is compatible with SNMPv1 andSNMPv2c.SNMPv3 adopts user name and password authentication.SNMPv1 and SNMPv2c adopt community name authentication. The SNMP packets containinginvalid community names are discarded. SNMP community name is used to define the relationshipbetween SNMP NMS and SNMP agent. Community name functions as password. It can limit
