Non-revertive mode

In non-revertive mode, the traffic channel is allowed to use the RPL, if it is not failed, after a switch condition clears. In the recovery from a Protection state, the RPL owner generates no response regarding the reception of NR messages. When other healthy nodes receive the NR message, there is no action in response to the message. After the operator issues a no command for non-revertive mode at the RPL owner, the non-revertive operation is cleared, WTB or WTR timer starts, as appropriate, and the RPL owner blocks its port to the RPL and transmits a R-APS (NR, RB) message. Upon receiving the R-APS (NR, RB), any blocking node should unblock its non-failed port.