The number of input datagrams for which this entity was not
their final IP destination and for which this entity
attempted to find a route to forward them to that final
destination. In entities that do not act as IP routers,
this counter will include only those datagrams that were
Source-Routed via this entity, and the Source-Route
processing was successful.
When tracking interface statistics, the counter of the
incoming interface is incremented for each datagram.
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
ipSystemStatsDiscontinuityTime.