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 an invalid code or persistently unacceptable codes in the K1 byte are received. 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.