PW redundancy for VPLS/VLL MCT allows the quick failover of traffic to the backup PWs. To support active and standby PWs to remote PEs, the Preferential status bit in the PW status TLV is exchanged to indicate whether the PW forwarding is active or standby.
To support PW redundancy, configure two VLL peers under one VLL instance. One PW is for each VLL peer. Among these PWs, an active-active PW is selected and used for traffic flow to the remote side. An active-active PW is selected based on the local and remote PW redundancy preferences. A remote PW redundancy preference is received by the PW status TLV. When the bit is set, it indicates PW forwarding standby. When the bit is cleared, it indicates PW forwarding active.