MIB: IF-MIB
The number of inbound packets which were chosen to be discarded
even though no errors had been detected to prevent their being deliverable to a higher-layer protocol.
One possible reason for discarding such a packet could be to free up buffer space.
Discontinuities in the value of this counter can occur at re-initialization of the management system,
and at other times as indicated by the value of ifCounterDiscontinuityTime.