US Patent 7127523 Spanning tree protocol traffic in a transparent LAN

A method for controlling a system of label-switched tunnels through a communication network, the method including pushing a signaling label onto a signaling frame at a first node in the network, and sending the signaling frame through the label-switched tunnels to one or more recipient nodes in the network. The signaling label is popped off the signaling frame at the one or more recipient nodes, which responsive to the signaling label, process the signaling frame so as to eliminate loops formed by the label-switched tunnels.