Holds valid ifIndex value of the interface through
which the notifications for the target with
Multicast/Link local address specified in the
snmpTargetAddrTAddress, is sent.
If snmpTargetAddrTAddress doesn't hold a Linklocal or
a Multicast target address then the value of this
object will be zero.
For the entries with snmpTargetAddrTAddress having
Link Local or Multicast address the
snmpTargetAddrStatus cannot be set to valid unless the
value for this object holds a valid ifIndex value.