SNMP messages

There are two types of Simplified Network Messaging Protocol (SNMP) messages: requests and traps.

SNMP requests are issued from a Network Management System (NMS) to an SNMP agent service on a host network device. The request can be a query for status of a particular object, as defined in a Management Information Base (MIB) file, of the host network device. A request can also be a command to set a variable, such as a specific value for an object defined in a MIB file. When the request is received, the SNMP agent responds with a message to the NMS that sent the request.

SNMP traps are unsolicited messages from the network device to the NMS. When a monitored condition on the network device reaches a specific value, as defined in a MIB file on the host device, the SNMP agent sends the trap to the NMS.