Bridge device and facility network

Abstract

A bridge device (-) which can effectively reduce the waste of the band resource in the upstream bus connected to a management device is realized by including: a first input/output port (); a second input/output port (); a group information keeping unit () to keep a group identifier and a correspondence between one or more terminal devices and the group identifier, the group identifier identifying a group that includes one or more terminal devices to be connected to the second input/output port (), the one or more terminal devices belonging to the group; an extended-request processing unit () to generate, when an extended-request frame including destination information corresponding to the group identifier for requesting state information of the one or more terminal devices belonging to the group is inputted to the first input/output port (), a request frame to be outputted from the second input/output port () to each of the one or more terminal devices belonging to the group, on the basis of the extended-request frame; and a relay processing unit () to output the request frame to the second input/output port () and output the extended-request frame to the extended-request processing unit ().