An apparatus including a first interface unit configured to perform frame communication processing with a ring network; a second interface unit configured to perform frame communication processing with a different network; a processing unit configured to convert a frame of a first format from the different network to a frame of a second format; a frame switching unit having at least one port connected to each of the first interface unit, the second interface unit and the processing unit and configured to switch the frame between ports; and a table configured to store frame identification information in correspondence with an output destination port identifier for an output port in the frame switching unit and frame conversion requirement information indicating whether conversion to the frame of the second format is required.