Patent ID: 8422493

Claim:
A network relay device for relaying communication for a regular terminal via a port, comprising: an acquiring module configured to acquire a regular layer 2 address representing a layer 2 address allocated to the regular terminal, a regular layer 3 address representing a layer 3 address allocated to the regular terminal, regular VLAN information representing a VLAN assigned to the regular terminal, and regular port information representing a port to which the regular terminal is connected; one or a plurality of relay lookup tables which identifies, based on a destination layer 3 address of target frame data, among the ports, an output port that outputs the target frame data and includes a regular terminal information storing module for authentication configured to store regular terminal information representing a combination of the acquired regular layer 2 address, the regular layer 3 address, the regular VLAN information, and the regular port information; and a determination process module configured to determine whether the combination of source layer 2 address, source layer 3 address, assigned VLAN, and reception port of target frame data received via the port is stored as the regular terminal information in the regular terminal information storing module included in the relay lookup table, wherein the regular terminal information stored in the regular terminal information storing module provided within the one or plurality of relay lookup tables is stored in different areas from areas where information used for transport processes is stored in the relay lookup table.