Patent ID: 7974223

Claim:
A method for communication via a ring network that includes a plurality of nodes associated with a Virtual Private LAN Service (VPLS), the method comprising: receiving at a first node in the ring network a data packet transmitted over a virtual LAN, the data packet comprising a virtual LAN identifier, which is one of: a VLAN ID and a port identifier; wherein the first node comprises a bridge node, and the data packet received at the first node comprises a destination address outside the ring network; mapping the virtual LAN identifier into a VPLS identifier (VPLS ID), wherein the VPLS ID has the same value for both unicast and multicast packets across all the nodes of the ring network; replacing the virtual LAN identifier with the VPLS ID in the data packet; reading the VPLS ID from the data packet at the first node; and responsively to reading the VPLS ID, forwarding the data packet from the first node to at least one second node among three or more of the nodes in the ring network that are associated with the VPLS; wherein forwarding the data packet comprises checking the destination address and the VPLS ID against a forwarding table to determine the at least one second node on the ring network to which the data packet should be forwarded; assigning a subset of the nodes of the ring network to serve the VPLS, wherein forwarding the data packet comprises, if the forwarding table does not include an entry corresponding to the destination address and the VPLS ID, multicasting the data packet to the subset of the nodes; wherein multicasting the data packet comprises setting a time-to-live (TTL) value of the data packet so that the data packet will reach all the nodes in the subset serving the VPLS without traversing at least one span of the ring network; and wherein setting the TTL value comprises determining a minimal number of hops required to reach all the nodes in the subset serving the VPLS, and setting the TTL value to the minimal number.