SNMP Test for routers is a tool which can query and monitor any SNMP-compatible device but it is especially designed to test SNMP router compatibility.
The first part of the test queries the system name and system description strings, the forwarding flag and enumerates all the exposed interfaces.
The 2nd part of the test monitors SNMP traps from the device (your system must be configured to receive traps from the device). While the monitoring is running, trigger some events e.g. connection and disconnection of the Internet line and see if those events are reported in the application.