Which SNMP operation is described as being used by an SNMP agent to inform the pre-configured SNMP manager of a certain event?

• A. GetRequest
• B. SetRequest
• C. GetResponse
• D. Trap

Answer: (B)

The main idea here is how SNMP communicates events to a manager. In SNMP, most actions are initiated by the manager (asking for data or changing settings), and the agent replies. However, when something noteworthy happens on the device, the agent can proactively send a notification to the manager. This notification is called a Trap. It’s an asynchronous, unsolicited message from the agent to the pre-configured manager to alert about an event (like an threshold being crossed or a interface status change). Traps are not responses to a request; they’re independent alerts. The other options describe manager-initiated operations: GetRequest asks for data, SetRequest changes a value, and GetResponse is the reply to a prior request. Therefore, the best choice is Trap.