The current operational status of the iSD.
'swMismatch' means that the iSD is up, but the software
version does not match the rest of the system. The correct
software version must be installed on this iSD to make it
enter the 'up' state.
'appError' means that the iSD is up, but the applicaion
is not functioning, i.e. the iSD does not handle traffic
correctly. Check the application specific MIBs for further
diagnostics.