| 摘要 |
The present invention is a relay device (layer 2 switch (20)) for forming a communications network, comprising: a plurality of communication ports (211, 212, ..., 21n) which transmit and receive frames; and a loop detection unit (22) which monitors for each communication port a frequency of reception of a control frame which is periodically transmitted from communication devices which form the communications network into the communications network, and instructs communication ports that have a receiving frequency that exceeds a threshold to halt transmission and reception of frames. |
