This object provide details on the protocol states
for this link as follows.
Changeback control(TCBC)
'tcbcBuffering': Changeback control is buffering data
on this link.
Changeover control(TCOC)
'tcocBuffering': Changeover control is buffering data
on this link
Link availability control(TLAC)
'tlacAdjacentSpRestarting': Adjacent Signalling point
is restarting.
'tlacEmergencyCoInProgress': Emergency changeover is in
progress on this link.
'tlacChangebackInProgress': Changeback is in progress
on this link.
'tlacChangeoverInProgress': Changeover is in progress
on this link.
'tlacChangeoverFailed': The last changeover operation
failed on this link.
'tlacInhibitRetry': Inhibit command will be retried.
'tlacManagementRequest': Management request in progress
for this link.
'tlacSpRestarting': Signalling point is in the process
of a restart.
Signalling routing control(TSRC)
'tsrcChangeOverComplete': Changeove request is complete.
'tsrcAdjacentSpRestart': Adjacent Signalling Point is
restarting.