Interworking an Ethernet Ring network with an Ethernet network with traffic engineered trunks (PBT network) enables traffic engineered trunks to be dual homed to the Ethernet ring network to enable for protection switching between active and backup trunk paths in the PBT network. In one embodiment, the active path will terminate at a first bridge node on the Ethernet ring network and the backup path will terminate at a second bridge node on the Ethernet ring network. Trunk state information is exchanged between the bridge nodes to enable the bridge nodes to determine which of the active and backup paths should be used to forward data on the trunk. Upon a change in trunk state, a flush message is transmitted on the Ethernet ring network to enable the nodes on the Ethernet ring network to relearn the path to the new responsible bridge node.