Repeater
A repeater efficiently transfers frames addressed to the same destination address when the frames are received at the same time by a plurality of ports, by performing a distribute-transfer process, when a difference between a size of each of the frames received by a normal port and an average size of those frames is within a preset range for all the frames, or an actual-measured communication speed of each of two ring ports is greater than a threshold. The distribute-transfer process distributes and transmits the frames to two communication paths from the two ring ports after receiving the frames at the two normal ports. The highest actual-measured communication speed of a ring port among other ring ports of the repeaters is considered as a communication efficiency parameter for selecting a broadest communication path for transmitting the frame. The frame(s) having the highest communication speed is/are distributed to the ring port connected to the broadest path.
1. A repeater for organizing a communication network, the repeater comprising:
a port section having a plurality of ports, the port section configured to transmit and receive frames;
a memory configured to store communication efficiency information and connection information for each of a plurality of communication nodes on the communication network; and
a repeat processor configured
to retrieve a destination address of a frame received by the port section,
to select one of the plurality of the ports of the port section to transmit the received frame based on the destination address and the connection information stored in the memory, and
to transmit the received frame from the selected port, wherein
the repeat processor is further configured to perform a distribute-transfer process when a plurality of frames having a same destination address is received by the port section, by
defining a plurality of communication paths to the same destination address by referencing the connection information stored in the memory,
selecting one or more of the plurality of communication paths as a broadest path based on a preset communication efficiency parameter, the communication efficiency information stored in the memory, and the connection information stored in the memory,
selecting one communication path as the broadest path having a high communication efficiency when more than one of the plurality of communication paths are selected as the broadest path,
distributing one of the plurality of frames having the same destination address and having a highest communication speed to a port in connection with the broadest path, wherein
the communication efficiency information indicates a communication efficiency of each of the plurality of ports of the repeater and of each of a plurality of other ports associated with the communication nodes, and wherein
the connection information indicates connections among the communication nodes on the communication network.
2. The repeater of claim 1 , wherein
the repeat processor is further configured to perform the distribute-transfer process when a difference between (i) a size of a frame addressed to the same destination address and (ii) an average size of the plurality of frames having the same destination address, is determined to be within a preset range.
3. The repeater of claim 1 , wherein
the repeat processor is further configured to perform the distribute-transfer process when the communication efficiency of each of a plurality of ring ports connected to the plurality of communication paths is greater than a preset threshold.
4. The repeater of claim 1 , wherein
the repeat processor is further configured to perform the distribute-transfer process by distributing the plurality of frames having the same destination address and not having the highest communication speed to a port not connected to the broadest path.
5. The repeater of claim 1 further comprising:
an information updater configured to update the communication efficiency information by obtaining communication efficiency data for the plurality of other ports associated with the communication nodes, wherein
the communication network is organized as a ring-shaped network, and
the information updater includes:
a transmitter configured to transmit from one of a pair of ports on the repeater, a self-addressed update frame that includes the communication efficiency data about the pair of ports on the repeater;
a transferer configured to transfer the self-addressed update frame to the other one of the pair of ports other than the receiving port by writing the communication efficiency data of the pair of ports to the received update frame, upon receiving the update frame that is transmitted from another node by one of the pair of ports; and
an update performer updating, upon receiving the self-addressed update frame by one of the pair of ports, the communication efficiency information stored by the memory by using the data written in the received update frame.
6. The repeater of claim 5 , wherein
the update performer updates, upon receiving by the pair of ports the update frame that is transmitted from the other node, the communication efficiency information stored by the memory by using the data written in the update frame when the update frame transmitted by the other node is received by the pair of ports.
7. The repeater of claim 1 , wherein
the memory stores a table with information indicating a relationship between the ports and the communication efficiency information.