Hitachi Metals, Ltd.

Apresia Systems, Ltd.

Kazutoshi Kariya

Shingo Sugawara

Kenji Aoshima

A traffic amount measuring unit measures the traffic amount of frames received in each of cycles, and outputs the measured traffic amount for each cycle. A plurality of frequency counters are provided so as to correspond to a plurality of ranges, and retain frequencies of each of the plurality of ranges, respectively. A frequency counter updating unit determines in which of the plurality of ranges the traffic amount output for each cycle is included, and updates the frequency of the frequency counter corresponding to the range obtained by the determination result.

Network apparatus

An LP table retains a combination of a physical port and a VLAN identifier in association with a logical port. When a frame is received at the physical port, a table processing unit acquires a logical port based on the LP table. An FDB processing unit learns a source MAC address contained in the received frame in association with the logical port acquired by the table processing unit to an FDB. A plurality of logical ports are set for the physical port by the LP table. A loop prevention unit prohibits frame relay between the plurality of logical ports set for the physical port.

Relay device and relay system

A relay device includes: a first port and a second port which are connected to a ring network; a relay path for relaying a frame between the first port and the second port; and a first monitoring point and a second monitoring point provided on a side close to the second port on the relay path. The first monitoring point monitors continuity between itself and the second monitoring point of a different device via the relay path of its own device by using a CCM frame based on Ethernet OAM. The second monitoring point monitors continuity between itself and the first monitoring point of a different device via the relay path of the different device by using the CCM frame.

Relay system and relay device

One external ports of the line cards are set as member ports of the same LAG. When monitoring a continuity between the member ports of the LAG and an outside of the device, a management card generates a first monitoring frame and transmits it to any line card corresponding to the LAG. The line card transmits the first monitoring frame to the outside of the device from the external port. When the line cards corresponding to the LAG receive a second monitoring frame from the outside of the device by the LAG, the line cards transmit the second monitoring frames to the management card.

Relay device

A ring control unit controls the ring network by transmitting and receiving a control frame through ring ports, and receives an address table deletion command via the control frame. When a first deletion command is received, an address table processing unit prohibits a learning process to the address table and then starts deleting the address table. Then, when a N-th (N is an integer of 2 or more) deletion command is received in a period before the completion of the deletion of the address table, the address table processing unit continues to execute the deletion of the address table.

Each of first and second monitoring points monitors the continuity between itself and outside of the device by use of a CCM frame. First and second internal monitoring points monitor the continuity between the first monitoring point and the second monitoring point inside the device by an internal continuity monitoring frame. When a first internal monitoring point or a second internal monitoring point does not receive the internal continuity monitoring frame within a predetermined period, a ring control unit instructs the first and second monitoring points to transmit a RDI frame or instructs them to stop transmission of a CCM frame.

A network relay device capable of shortening retrieval time for an address table or reducing a capacity of the address table is provided. When a transmission-source address of a frame received at first and second port groups is learned, a frame processing unit performs a hash calculation by using the transmission-source address and a first internal identifier. Then, an internal identifier etc., corresponding to the receiving port is registered in an entry inside an address table obtained by the hash calculation. On the other hand, when a transmission-destination address of a frame received at the first and second pot groups is retrieved, the frame processing unit performs a hash calculation by using the transmission-destination address and, reads out an entry inside the address table obtained by the hash calculation, and compares the internal identifier inside the address table with an internal identifier corresponding to the receiving port.

Network relay device

When a first line card receives a frame at a port, the line card refers to monitoring results by internal communicability monitoring units of other second to fourth line cards and a monitoring result by an internal communicability monitoring unit of its own, determines a first of a transmission destination from band limiting units of other line cards based on the monitoring results, and transmits the frame. The second line card limits the communication band of the frame by the first band limiting unit of its own, and transmits the frame to a predetermined port. If any fault is detected in the communicability in the internal communicability monitoring table to/from the second line card as the communication counterpart, and, if the communicability to/from the third line card as the communication counterpart is normal, the first line card changes the transmission destination into the second band limiting unit.

Growing community of inventors

Tsuchiura, Japan

Kazutoshi Kariya