Drop SNMPv3 traps at early filter. trapFilter.conf only catch SNMPv2 but in 2020 V3 is a must

[opensky7]

In 2020(and prior) more and more device use SNMPv3 and send traps in V3 as request by security team.  But if you have a flood in SNMPv3 the file trapFilter.conf as no used because it process only SNMP V2c and that early stage filter cannot see encrypted V3 traps. 

Then if you have a flood it will hit your flooding engine and will "shut down" trap processing, probably even the other V1/V2 traps, to protect itself.

Then I request to add a post decryption V3 filtering but prior to the flood engine.

For now we can use nnmtrap.conf to drop traps after the flooding engine but that setup is not optimal.

[Jean-Patrick Kong]

This is a critical feature to have for NNMi  for all of big enterprises.

[AkashDeep]

The idea has received an initial review to ensure adherence to our idea submission and community guidelines. More information may be needed at this stage, and we expect the community to help prioritize the idea with comments and community support (votes/kudos).