Patent ID: 7983150

Claim:
A method for communication over a bi-directional ring network that includes nodes connected by spans of the ring network, the method comprising: provisioning a virtual private local area network service (VPLS) to serve users over the bi-directional ring network, the VPLS comprising connection termination points provisioned respectively on a plurality of the nodes so as to connect each of the plurality of the nodes to a second network external to the ring network; activating a selected connection termination point, to establish a connection between the bi-directional ring network and the second network; as long as the nodes and spans are fully operational, maintaining all of the connection termination points except the selected connection termination point in a deactivated state, so that only the selected connection termination point to the second network is active; exchanging messages among the nodes indicative of: a failure in at least two spans of the ring network causing a segmentation of the ring network and leading to an isolation of a first node of the ring network from at least one second node of the ring network; and responsively to the messages, activating at least one of the deactivated connection termination points so as to overcome the segmentation and maintain connectivity of the first node with the at least one second node of the ring network, without creating a loop in the VPLS via the second network.