Reference : RFC 2863: The Interfaces Group MIB - ifHCOutUcastPktsThe total number of packets that higher-level protocols
requested be transmitted, and that were not addressed
to a multicast or broadcast address at this sub-layer,
including those that were discarded or not sent.
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
'last-clear'.