Abstract: A server detects an abnormality of a VM being a transfer destination of a packet; rewrites, when the VM is switched, a first relationship between a transfer destination MAC address and a port number of the VM before switching to a first relationship between the MAC address and a port number of the switched VM; decides, from the port number being matched based on the rewritten first relationship and a second relationship among a port number of the switched VM, a transfer destination MAC address, and a transfer destination IP address, the transfer destination MAC address and the transfer destination IP address of the switched VM; rewrites the transfer destination MAC address and the transfer destination IP address included in the header of the packet received from a network to the decided MAC address and the IP address; and transfers the rewritten packet to the switched VM.

Abstract: A control method performed by a network device includes replenishing a token to a token bucket and updating a timestamp indicating an execution time point of a meter operation when a user packet is received from another device, generating a dummy packet different from the user packet for every certain time period, in response to the dummy packet, replenishing the token to the token bucket, updating the timestamp, and discarding the dummy packet, controlling traffic in accordance with the token within the token bucket.

Abstract: A communication device includes a processor that is operative to perform actions, including, determining whether a failure occurs in a regular communication channel to transmit a packet to another communication device, selecting, upon determining that the failure occurs in the regular communication channel, a backup communication channel for transmitting the packet, determining, upon selecting the backup communication channel, whether the backup communication channel is shared by the regular communication channel and another regular communication channel, changing, upon determining that the backup communication channel is shared, a priority assigned to the packet transmitted from the regular communication channel to the backup communication channel, and controlling the transmission of the packet in accordance with the changed priority.

Abstract: A reception apparatus includes a receiver configured to receive a packet including a label and quality information indicating communication quality for the packet. The reception apparatus also includes a processor configured to allocate a priority to the received packet based on a combination of the label and the quality information included in the received packet and a transmitter configured to supply the packet to which the priority is allocated to a switch that performs transfer control to a packet based on its priority.

Abstract: There is provided a packet transmission device which comprises a packet transfer processing part and a control part. The packet transfer processing part includes a table memory comprising a path selection table, a link status table, and a node status table. In these tables, information of each of paths, links, and nodes are stored and linked each other. A link/node status monitoring part in the control part monitors a packet outputted from the packet transfer processing part transmission and detects a fault occurred in a transmission of the packet. The fault is reflected on the information of paths in the tables only by updating the information of links and nodes and the path for packets outputted from the device is assigned in a short time.

Abstract: A communication apparatus is connected to a network and identifies a flow of a frame input thereto and outputs the frame to a port. The communication apparatus includes: a flow identifying unit that obtains a flow identifier of the flow to which the frame belongs, and that obtains, based on the flow identifier, a hash rule corresponding to the flow identifier; a transfer destination controller that obtains by calculation a hash value of the frame by making use of the hash rule obtained by the flow identifying unit and that decides on an output port for the frame based on combination of the flow identifier and the hash value; and a frame output unit that outputs the frame to the output port decided by the transfer destination controller.

Abstract: A packet processing apparatus includes a plurality of communication connecting unit each connected with a communication partner apparatus using one of a work path and a protection path, connecting unit for connecting, using a data bus, the plurality of communication connecting unit with one another; determination unit for, when a packet sent from the communication partner apparatus is received by one of the communication connecting unit, determining whether the packet is a maintenance packet that is used for monitoring a connection state with the communication partner apparatus; and transmitting unit for, when it is determined that the packet is a maintenance packet by the determination unit, transmitting the maintenance packet to the plurality of communication connecting unit using the data bus via the connecting unit.

Abstract: A packet forwarding device includes a storage that stores a path selection table in which link numbers of a Work path and a Protection path for each flow number of a transfer packet, a flag that indicates whether the link is made up of a plurality of physical lines, a link aggregation number that identifies an aggregation of the plurality of physical lines, and destination information are set in association with one another, a link status table, a node status table, and an LAG status table, and a path selection processor that selects a path that outputs the packet on the basis of the information.

Abstract: A reception apparatus includes a receiver configured to receive a packet including a label and quality information indicating communication quality for the packet. The reception apparatus also includes a processor configured to allocate a priority to the received packet based on a combination of the label and the quality information included in the received packet and a transmitter configured to supply the packet to which the priority is allocated to a switch that performs transfer control to a packet based on its priority.

Abstract: An aspect of the embodiments related to a packet transmission apparatus includes a user identification unit for identifying the user of an input user flow upon input of the user flow containing communication packets and maintenance packets, a maintenance packet extraction unit for extracting the maintenance packets from the user flow of the user identified by the user identification unit, a maintenance packet output control unit for controlling the transparent output of the maintenance packets extracted by the maintenance packet extraction unit based on the monitor rate setting, and a control unit for monitoring and controlling the user flow of the particular user based on the maintenance packets of the user transparently output by the maintenance packet output control unit.

Abstract: A communication device includes a processor that is operative to perform actions, including, determining whether a failure occurs in a regular communication channel to transmit a packet to another communication device, selecting, upon determining that the failure occurs in the regular communication channel, a backup communication channel for transmitting the packet, determining, upon selecting the backup communication channel, whether the backup communication channel is shared by the regular communication channel and another regular communication channel, changing, upon determining that the backup communication channel is shared, a priority assigned to the packet transmitted from the regular communication channel to the backup communication channel, and controlling the transmission of the packet in accordance with the changed priority.

Abstract: A communication apparatus is connected to a network and identifies a flow of a frame input thereto and outputs the frame to a port. The communication apparatus includes: a flow identifying unit that obtains a flow identifier of the flow to which the frame belongs, and that obtains, based on the flow identifier, a hash rule corresponding to the flow identifier; a transfer destination controller that obtains by calculation a hash value of the frame by making use of the hash rule obtained by the flow identifying unit and that decides on an output port for the frame based on combination of the flow identifier and the hash value; and a frame output unit that outputs the frame to the output port decided by the transfer destination controller.

Abstract: A packet forwarding device includes a storage that stores a path selection table in which link numbers of a Work path and a Protection path for each flow number of a transfer packet, a flag that indicates whether the link is made up of a plurality of physical lines, a link aggregation number that identifies an aggregation of the plurality of physical lines, and destination information are set in association with one another, a link status table, a node status table, and an LAG status table, and a path selection processor that selects a path that outputs the packet on the basis of the information.

Abstract: A packet processing apparatus includes a plurality of communication connecting unit each connected with a communication partner apparatus using one of a work path and a protection path, connecting unit for connecting, using a data bus, the plurality of communication connecting unit with one another; determination unit for, when a packet sent from the communication partner apparatus is received by one of the communication connecting unit, determining whether the packet is a maintenance packet that is used for monitoring a connection state with the communication partner apparatus; and transmitting unit for, when it is determined that the packet is a maintenance packet by the determination unit, transmitting the maintenance packet to the plurality of communication connecting unit using the data bus via the connecting unit.

Abstract: An aspect of the embodiments related to a packet transmission apparatus includes a user identification unit for identifying the user of an input user flow upon input of the user flow containing communication packets and maintenance packets, a maintenance packet extraction unit for extracting the maintenance packets from the user flow of the user identified by the user identification unit, a maintenance packet output control unit for controlling the transparent output of the maintenance packets extracted by the maintenance packet extraction unit based on the monitor rate setting, and a control unit for monitoring and controlling the user flow of the particular user based on the maintenance packets of the user transparently output by the maintenance packet output control unit.

Abstract: There is provided a packet transmission device which comprises a packet transfer processing part and a control part. The packet transfer processing part includes a table memory comprising a path selection table, a link status table, and a node status table. In these tables, information of each of paths, links, and nodes are stored and linked each other. A link/node status monitoring part in the control part monitors a packet outputted from the packet transfer processing part transmission and detects a fault occurred in a transmission of the packet. The fault is reflected on the information of paths in the tables only by updating the information of links and nodes and the path for packets outputted from the device is assigned in a short time.

Abstract: A sub-rate time switch switches a digital multiplexed signal having a basic-rate signal included in a first time slot of the digital multiplexed signal and N sub-rate signals included in a second time slot thereof where N is an integer. Each the sub-rate signals has a sub-rate which is equal to 1/N times a basic rate of the basic rate signal. A speech path memory temporarily stores the digital multiplexed signal input to the sub-rate time switch. A channel signal is read out from the speech path memory and has a plurality of channels corresponding to time slots of the digital multiplexed signal. A control part controls write and read operations of the speech path memory so that the channel signal includes N consecutive channels. Each of the N consecutive channels includes N identical sub-rate signals, and each of the N identical sub-rate signals corresponds to one of the N sub-rate signals included in the second time slot of the digital multiplexed signal.