US 12,309,021 B2
Relay device, relay system, relay method and computer-readable recording medium that reduce a traffic load on a communication device
Ryohei Kuba, Tokyo (JP); Sachiko Taniguchi, Tokyo (JP); and Ryusuke Kawate, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Filed by MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Filed on Jul. 19, 2022, as Appl. No. 17/867,808.
Application 17/867,808 is a continuation of application No. PCT/JP2020/010996, filed on Mar. 13, 2020.
Prior Publication US 2022/0353132 A1, Nov. 3, 2022
Int. Cl. H04L 41/0654 (2022.01)
CPC H04L 41/0654 (2013.01) 9 Claims
OG exemplary drawing
 
1. A relay device comprising:
a port that is connected to a trunk circuit included in a trunk network which is made redundant;
a port that is connected to a branch circuit included in a branch network whereto a communication device is connected;
a memory to store an address of the communication device, and a port number indicating the port corresponding to the address; and
processing circuitry to:
start clocking in a case wherein the memory is cleared when a transfer path of the trunk network to transfer a frame received via one of the ports is switched;
search whether the port number corresponding to the address identical with a destination address included in the frame is stored in the memory, and obtain the port number stored when the port number is stored; and
transfer the frame to the port indicated by the port number when the searching obtains the port number; transfer the frame to a port that is connected to the trunk circuit among the port connected to the trunk circuit and a port connected to the branch circuit when the searching fails to obtain the port number, and when a clocked time is within a set time; and transfer the frame to the port connected to the trunk circuit and the port connected to the branch circuit when the searching fails to obtain the port number, and when the clocked time exceeds the set time, wherein
the memory stores information on a port attribute indicating an attribute of a circuit whereto the port indicated by the port number corresponding to the address is connected, and when the information on the port attribute stored in the memory is information indicating that the port indicated by the port number corresponding to the port attribute is the port connected to the branch circuit, even in a case wherein the memory is cleared when the transfer path is switched, the port number corresponding to the port attribute is not cleared.