An apparatus includes means for transmitting a packet, through one of a plurality of pseudo wires, from a PW ingress node thereof to a PW egress node thereof. Each of the plurality of pseudo wires is a communication path for transmitting a packet between a pair of end nodes included in three or more nodes communicably connected via a tunnel in a packet switched network. The PW ingress node is one of the pair of end nodes from which the packet comes into the one of the plurality of pseudo wires, and the PW egress node is the other one of the pair of end nodes from which the packet goes out thereof. The apparatus further includes means for extracting a packet transmitted through the one of the plurality of pseudo wires from among packets being transmitted through the tunnel.