Patent ID: 8441921

Claim:
A method of providing protection switching on a backbone network, the method comprising: configuring a service instance table for a first port of a first bridge connecting a backbone network to an external network, wherein the service instance table includes a Virtual Local Access Network (VLAN) identifier entry for each of one or more service instances on the backbone network supported by the first bridge; mapping data traffic received at the first bridge from the external network onto a first trunk of the backbone network by setting a VLAN identifier entry for a first service instance in the service instance table to a value for a working entity VLAN that corresponds to the first trunk, wherein the first trunk comprises a pair of unidirectional paths connecting the first bridge to a second bridge on the backbone network; transmitting data traffic received from the external network to the second bridge on the first trunk in accordance with the mapping; monitoring the first trunk for faults by exchanging continuity check messages with the second bridge over the first trunk, wherein an indicator included in each of the continuity check messages indicates whether a fault has occurred on the first trunk; upon detecting a fault on the first trunk, remapping data traffic for the first service instance from the first trunk onto a second trunk that connects the first bridge to the second bridge by changing the VLAN identifier entry for the first service instance from the value for the working entity VLAN to a value for a predetermined protection entity VLAN wherein the protection entity VLAN corresponds to the second trunk; and transmitting data traffic received from the external network to the second bridge on the second trunk in accordance with the remapping.