Metro Ethernet

GMPLS Protection and Restoration Mechanisms

GMPLS introduces the necessary features in routing, signaling, and link management to support the fault management required in optical and electronic networks. Fault management requires the following capabilities:

• Fault detection— For optical networks, fault detection can be handled via mechanisms such as loss of light (LOL) and optical signal-to-noise ratio (OSNR) at the optical level, and bit error rate (BER), SONET/SDH Alarm Indicator Signal (AIS), or LOL at the SONET/SDH level.

• Fault isolation— For GMPLS, LMP can be used for fault isolation. The LMP fault-management procedure is based on sending ChannelActive and ChannelFail messages over the control channel. The ChannelActive message is used to ...