Indicates whether cieLinkUp/cieLinkDown
or standard mib-II defined linkUp/Down or
both, notifications should be generated
for the interfaces in the system.
'standard' - only generate standard defined
mib-II linkUp/linkDown notification
if 'ifLinkUpDownTrapEnable' for
the interface is 'enabled'.
'cisco' - only generate cieLinkUp/cieLinkDown
notifications for an interface if
the 'ifLinkUpDownTrapEnable' for the
interface is 'enabled'.
If both bits are selected then linkUp/linkDown and
cieLinkUp/cieLinkDown are both generated for an
interface if the 'ifLinkUpDownTrapEnable' for the
interface is 'enabled'.