Failure Notification in a Network Having Serially Connected Nodes

A link state protocol controlled Ethernet network having data plane multicast capability, the network comprising:

• a first node configured to issue a frame containing a control message signifying a local topology change, the frame being addressed to a control plane specific multicast group address;
• a second node configured:
• to receive from the first node the frame containing the control message;
• to perform a reverse path forwarding check on the frame to determine if the frame arrived at the second node on a port expected for multicast frames arriving from the first node;
• to discard the frame immediately when the frame fails the reverse path forwarding check;
• and
• to forward the frame toward a plurality of downstream nodes in the network according to forwarding state stored in a forwarding information base at the second node only when the frame passes the reverse path forwarding check.

A node for a link state protocol controlled Ethernet network having a data plane multicast capability, the node comprising:

• a routing element configured to receive a frame containing a control message signifying a local topology change addressed to a control plane specific multicast group address from first other node of the network;
• and
• a reverse path forwarding check element configured:
• to perform a reverse path forwarding check on the frame to determine if the frame arrived at the second node on a port expected for multicast frames arriving from the first node;
• to discard the frame immediately when the frame fails the reverse path forwarding check;
• and
• to forward the frame toward a plurality of downstream nodes in the network according to forwarding state stored in a forwarding information base at the second node only when the frame passes the reverse path forwarding check.

A method of operating a node for a link state protocol controlled Ethernet network having a data plane multicast capability, the method comprising:

• receiving a frame containing a control message signifying a local topology change addressed to a control plane specific multicast group address from first other node of the network;
• and
• performing a reverse path forwarding check on the frame to determine if the frame arrived at the second node on a port expected for multicast frames arriving from the first node;
• discarding the frame immediately when the frame fails the reverse path forwarding check;
• and
• forwarding the frame toward a plurality of downstream nodes in the network according to forwarding state stored in a forwarding information base at the second node only when the frame passes the reverse path forwarding check.