To trigger the alive link diagnosis operation between
the Master device and the current selected EP device.
Maintain the connection while running the diagnosis.
The diagnosed results include the on-line SNR/LineRate/RxPower
for both the DnLink:'Transmit'(Tx)-to-EP and
UpLink:'Receive'(Rx)-from-EP operation.
The SNMP manager can set this value to activate(1) to
start the diagnosis procedure. The status (eocBrEPOnlineDiagStatus)
will go from inProgress(1) status back to the initial
normalOrComplete(0) status.