| Description | The current status of the APS group.
modeMismatch
Modes other than 1+1 unidirectional monitor protection
line K2 bit 5, which indicates the architecture and K2
bits 6-8, which indicate if the mode is unidirectional
or bidirectional. A conflict between the current local
mode and the received K2 mode information constitutes
a mode mismatch.
channelMismatch
This bit indicates a mismatch between the transmitted
K1 channel and the received K2 channel has been detected.
psbf
This bit indicates a Protection Switch Byte Failure (PSBF)
is in effect. This condition occurs when either an
inconsistent APS byte or an invalid code is detected. An
inconsistent APS byte occurs when no three consecutive K1
bytes of the last 12 successive frames are identical,
starting with the last frame containing a previously
consistent byte. An invalid code occurs when the incoming
K1 byte contains an unused code or a code irrelevant for
the specific switching operation (e.g., Reverse Request
while no switching request is outstanding) in three
consecutive frames. An invalid code also occurs when the
incoming K1 byte contains an invalid channel number in
three consecutive frames.
feplf
Modes other than 1+1 unidirectional monitor the K1 byte
for Far-End Protection-Line failures. A Far-End
Protection-Line defect is declared based on receiving
SF on the protection line.
extraTraffic
This bit indicates whether extra traffic is currently being
accepted on the protection line. |