Abstract: A network system forms a computer network, and includes: a collecting unit; a calculating unit; and a display unit. The collecting unit collects power consumption information from a connecting device. The power consumption information shows power consumption of the connecting device. The calculating unit calculates power consumption of the computer network based on the collected power consumption information. The calculated power consumption is itemized into constituent units based on a configuration of the computer network. The display unit displays the calculated power consumption.

Abstract: In a bandwidth policing apparatus which accommodates a large number of user groups, bandwidth policing for each user group is performed at high speed. When there is any extra bandwidth in bandwidth for a user group, the contracted committed information rate for each user is guaranteed invariably while using this effectively. The bandwidth policing apparatus accumulates packets of a plurality of user groups under bandwidth policing in the same packet accumulate FIFO. Also, for a packet which does not exceed the contracted bandwidth for each user, the contracted bandwidth for each user is guaranteed by deciding that the packet does not exceed the contracted bandwidth for each user group.

Abstract: A network enables a transfer path to be formed between nodes in the network so as to transfer frames. A terminal for transmitting frames located outside the transfer path, upon transmitting a frame through the transfer path, writes the transfer path selection information related to the transfer path and the output line information related to the output line from the terminating node of the transfer path in the frame according to the destination information set in the frame and transmits the frame to the destination. The starting node of the transfer path decides the transfer path used for transferring the frame according to the transfer path selection information set in the frame to transmit the frame while the terminating node of the transfer path decides the output line used to output the frame according to the output line set in the frame, thereby transmitting the frame to the output line.

Abstract: A flow classifier having a flow CAM having plural flow entries, a search key generator for generating a search key of a format which differs by a flow condition, and a table holding a flow search result corresponding to an address of respective flow entry of CAM, in which access is made to CAM by the search key of a variable format including at least one header information item extracted from a packet header and the flow search result is obtained from the table in accordance with the address of the flow entry coinciding with the search key outputted from CAM to thereby constitute high speed formation of flow classifying by a variety of flow conditions.

Abstract: An edge router measures a traffic volume inputted into a network, and the measurement result is notified to a network management server. If the network management server judges that the notified traffic volume is “smaller” than a capacity of a second core router, it will direct a first core router to shift to a power saving mode. The first core router notifies the edge router of the shift to the power saving mode, and the edge router updates a routing table so that the packet to the first core router may be bypassed to the second core router. The first core router shifts to the power saving mode that does not perform packet transfer, and reduction in electric power is realized.

Abstract: To provide a packet forwarding device which minimizes degradation in packet forwarding performance at the time of execution of filtering there is provided a technique in which a destination decision processing unit of a destination decision and filtering unit decides whether to execute filtering on the basis of at least one of an input interface, an input port number, an output interface, and an output port number of an input packet and a plurality of pieces of information constituting the header of the packet. A filtering unit executes filtering only for a packet for which execution of filtering is decided. The packet forwarding device with the destination decision and filtering unit need not execute filtering for all packets and can minimize degradation in packet forwarding performance caused by filtering.

Abstract: A policing device having a table storing monitored bandwidth, packet history information for each importance level, and the allocation weight of the monitored bandwidth for each importance level, a policing table control circuit for reading out these items of information into each storage of a policing unit when a packet is inputted, and a calculation unit for judging the bandwidth of the input packet as being conformant or non-conformant to the contract on the basis of these items of information, thereby to control the bandwidth at each importance level.

Abstract: A packet forwarding apparatus 200 transmits an inputted packet A to a first output port that is one of a plurality of output ports and transmits a dummy packet A storing the packet length of packet A to the other output port. A shaping unit 100-1 corresponding to the first output port uses the packet length of the packet A and a shaping unit 100-2 corresponding to the port other than the first output port uses a packet length in the dummy packet A so as to control the bandwidth of the packet A to be transmitted, thus controlling the total bandwidth of the packet A.

Abstract: To provide a packet forwarding device which minimizes degradation in packet forwarding performance at the time of execution of filtering there is provided a technique in which a destination decision processing unit of a destination decision and filtering unit decides whether to execute filtering on the basis of at least one of an input interface, an input port number, an output interface, and an output port number of an input packet and a plurality of pieces of information constituting the header of the packet. A filtering unit executes filtering only for a packet for which execution of filtering is decided. The packet forwarding device with the destination decision and filtering unit need not execute filtering for all packets and can minimize degradation in packet forwarding performance caused by filtering.

Abstract: A technique capable of controlling packets to be output to a plurality of ports is provided. Disclosure is made of a packet forwarding apparatus for distributing packets received from a physical port to be transmitted over a plurality of physical ports, which includes a transmitting/receiving unit for transmitting/receiving packets via a physical port, a port group decision unit for deciding a port group corresponding to a plurality of physical ports, and a port group control unit for controlling flow of packets for each port group decided by the port group decision unit.

Abstract: A packet forwarding apparatus which quickly selects a plurality of control information entries to be applied according to header information of an input packet and concurrently performs various the header processing functions. The packet forwarding apparatus comprises a flow retrieval unit which compares header information of the input packet with plural sets of flow identification conditions and concurrently outputs various flow identifiers appropriate to the input packet, various header processing units corresponding to the flow identifiers, and a packet forwarding control unit for controlling forwarding of input packets according to control information outputted from at least one of the header processing units. While each of the header processing units has an information table containing plural information entries, reads a single information entry from the information table according to the flow identifier outputted from the flow retrieval unit, and executes a prescribed arithmetic operation.

Abstract: A bandwidth monitoring device for use in a network for transferring priority packets in preference to non priority packets as far as the amount of the priority packets is within a contract bandwidth established between a network user and a network operator, comprising a bandwidth check result decision unit for detecting whether the bandwidth of the priority packets is less than the contract bandwidth, and a DSCP decision unit for determining that a non priority packet may be transferred as a priority packet when the bandwidth of the priority packets is less than the contract bandwidth thereby to sufficiently use the contract bandwidth.

Abstract: A policing device having a table storing monitored bandwidth, packet history information for each importance level, and the allocation weight of the monitored bandwidth for each importance level, a policing table control circuit for reading out these items of information into each storage of a policing unit when a packet is inputted, and a calculation unit for judging the bandwidth of the input packet as being conformant or non-conformant to the contract on the basis of these items of information, thereby to control the bandwidth at each importance level.

Abstract: A packet forwarding apparatus is provided which can minimize traffic detoured to a backup path liable to be degraded in communication quality in the event of a link failure to thereby improve the communication quality. To this end, a technique is provided in which an output label decision unit and an output physical port ordinal number search unit which are included in a destination decision unit decide, from a header of an input packet, an output label of the packet, a first logical link to which the packet is to be outputted and a first physical link constituting the first logical link. When a failure takes place in the first physical link, the detour decision unit changes the output label to a backup label and the first physical link to a second physical link constituting a second logical link.

Abstract: A packet forwarding device changes packet transfer performance according to a packet load, and ensures communication quality of an important packet while transfer performance is made minimum to suppress power consumption. The packet forwarding device includes a measuring section to measure the packet load for each packet importance degree, an estimation section to estimate a future packet load for each importance degree based on the measurement result, a performance determination section to determine performance for an operation based on the estimated load, which are provided in, for example, a traffic estimation/performance determination section. Reduction in the power consumption and assurance of the communication quality of the important packet are realized by a minimum performance determination based on an important packet estimation load in the performance determination section and a preferential process of the important packet in the packet forwarding device.

Abstract: A bandwidth monitoring device for use in a network for transferring priority packets in preference to non priority packets as far as the amount of the priority packets is within a contract bandwidth established between a network user and a network operator, comprising a bandwidth check result decision unit for detecting whether the bandwidth of the priority packets is less than the contract bandwidth, and a DSCP decision unit for determining that a non priority packet may be transferred as a priority packet when the bandwidth of the priority packets is less than the contract bandwidth thereby to sufficiently use the contract bandwidth.

Abstract: A high quality network is provided that eliminates the sorting time for sorting through registering look-up conditions, such as source and destination MAC addresses, in a content addressable memory, by generating a routing or flow control look-up key, and then selectively activating some of the physical banks in the content addressable memory with the look-up key during look-up for the look-up conditions. The look-up key is generated by extracting a part or all of the data contained in a packet header.

Abstract: A power-saving packet forwarding device realizing electric power that accords to the number of lines in which communication is performed and a traffic volume inputted from the lines. A header processing unit with which the packet forwarding device is equipped has a plurality of packet processing circuits for performing a packet processing. A line number decision circuit monitors the number of lines in which communication is performed and a traffic volume inputted from the line, and decides presence or absence of an operation of a packet processing circuit. Based on this decision result, a power supply and a clock of the packet processing circuit that does not need to operate are interrupted, and accordingly power saving of the packet forwarding device is realized.

Abstract: When a packet arrives at a shaping unit 500, a discard control unit 510 judges whether to “store” or “discard” the arrived packet. Packets judged to be “stored” are stored into a packet storage FIFO buffer 520 and sent out within a transmission bandwidth greater than the total sum of user-by-user minimum bandwidths. A bandwidth check unit 600 checks bandwidth per user and judges packets that fall within the bandwidth to be high priority packets and packets that fall outside the bandwidth to be low priority packets. If a large quantity of packets are stored into the packet storage FIFO buffer 520, the discard control unit 510 determines that low priority packets are exclusively “discarded,” thus securing high priority packets from being discarded. Thereby, the shaping unit 500 ensures proper packet transmission within user-specific minimum bandwidth.

Abstract: A packet transfer apparatus having: a flow detector 30 for identifying a flow to which an input packet belongs from header information of the input packet and outputting a flow bundle identifier peculiar to the identified flow or a flow bundle identifier common to the identified flow and at least another flow; and a controller 40 having an information table 43 including a plurality of information entries corresponding to the flow bundle identifier, for reading out one of the information entries from the information table on the basis the flow bundle identifier received from the flow detector performing a predetermined computing process.