Network, router device, route updating suppression method used for the same, and program thereof

The router (1) 2-1-2-n) and routing processing unit (4) introduces the virtual port between the network interface (3-1-3-n). The virtual port (3-1-3-n) is used to the routing processing unit (4) concealed network interface (2-1-2-n) is of collision's and. (2-1-2-n) Is a virtual interface in aggregate of each network interface. The virtual port (3-1-3-n), manufacturing of the running condition, an availability status and impact and the state of the link exhibits. The impact of ACK/NAK, virtual port (3-1-3-n) not to change the routing processing unit (4) informing link state.