The configuration status of this port.
Setting this object to the value invalid(4)
has the effect of invalidating the corresponding
entry in the atportTable. That is, it
effectively disassociates the mapping identified
with said entry. It is an
implementation-specific matter as to whether the
agent removes an invalidated entry from the table.
Accordingly, management stations must be
prepared to receive from agents tabular
information corresponding to entries not
currently in use. Proper interpretation of such
entries requires examination of the relevant
atportStatus object.