Abstract: It is intended to reduce a power consumption without degrading a communication quality of a packet transfer device. One or more of a receiver, a switch unit, and a transmitter include a QoS control circuit for applying QoS control to received packets. There is provided a power saving operation mode that enables power saving operation by changing a grain size of the QoS control according to a flow rate of the packets, and controlling whether or not to supply an electric power to the QoS control circuit or a part of the QoS control circuit, according to the flow rate of the packets.

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 packet switch for switching variable length packets, wherein each of output port interfaces includes a buffer memory for storing transmission packets, a transmission priority controller for classifying, based on a predetermined algorithm, transmission packets passed from a packet switching unit into a plurality of queue groups to which individual bandwidths are assigned respectively, and queuing said transmission packets in said buffer memory so as to form a plurality of queues according to transmission priority in each of said queue groups, and a packet read-out controller for reading out said transmission packets from each of said queue groups in the buffer memory according to the order of transmission priority of the packets while guaranteeing the bandwidth assigned to the queue group.

Abstract: A relay device of relaying a communication packet is disclosed, which comprises: an input module configured to receive the communication packet as an input; a buffer configured to have a plurality of queues and temporarily accumulated the received communication packet; a sorter configured to sort the received communication packet to one of the plurality of queues, depending on a specific value obtained by a predetermined function that gives an aggregate output from an input which is transfer information regarding transfer of the communication packet; and a band controller configured to control a bandwidth for each of the plurality of queues and output communication packets accumulated in the plurality of queues for transmission of the communication packets. This ensures the quality of service, while saving the capacity of the buffer used for the queues.

Abstract: A packet switch for switching variable length packets. Each output port interface of the packet switch includes a buffer memory, a transmission priority controller, and a packet readout controller. The buffer memory stores transmission packets. The transmission priority controller classifies, based on a predetermined algorithm, transmission packets passed from a packet switching unit into a plurality of queue groups to which individual bandwidths are assigned respectively, and queues the transmission packets in the buffer memory so as to form a plurality of queues according to transmission priority in each of the queue groups. The packet readout controller reads the transmission packets from each of the queue groups in the buffer memory according to the order of transmission priority of the packets while guaranteeing the bandwidth assigned to the queue group.

Abstract: A traffic shaper which includes a cell buffer for temporarily storing an ATM cell arrived thereat, a first calculator for calculating an estimated cell sending time according to a VC contracted bandwidth, a second calculator for calculating an estimated cell sending time according to a VP contracted bandwidth, a binary tree VP sorting circuit for determining VP to be sent in top priority, a binary tree VC sorting circuit for determining VC to be sent in top priority, and a sending circuit for sending a cell in which the determined VP and VC are both brought to a transmittable state. The VP estimated sending time is revised according to the VC estimated sending time.

Abstract: A network management/apparatus connected to a plurality of packet relay apparatuses constituting a group through a network includes an energy saving level calculation unit for calculating an energy saving level of each of the packet relay apparatuses on the basis of a CPU usage ratio of the packet relay apparatus managed or a difference between the present energy saving level and the energy saving level of minimum guarantee of the packet relay apparatus, and an energy saving function setting unit for setting an energy saving function of the packet relay apparatuses on the basis of the energy saving level calculated by the energy saving level calculation unit.

Abstract: A network controller, capable of high-speed extraction of malicious traffic from networks and determining characteristics of such traffic, includes a unit for accumulating a number of packets for each arbitrary itemset included in the header portions of packets to be transferred, and a unit for determining whether the accumulated value obtained by the accumulating unit exceeds a predetermined threshold, and determines the types of packets to be transferred from accumulated values of the itemset and an itemset different from the itemset when the number of packets exceed a threshold.

Abstract: A switching system includes a data collection device, one or more switching devices. The data collection device is for collection of first data subject to specific processing. The switching devices directly or indirectly connected to the data collection device. At least one of the switching devices includes a determination module that determines whether received data is the first data or is second data which is not subject to the specific processing, and a marking module that puts first marking on the received data determined to be the first data. The switching devices respectively includes a transferring processor that executes a first transfer process for sending the received data to the data collection device when the received data has the first marking, and a second transfer process that sends the received data to the specified destination when the received data does not have the first marking.

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 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: It is intended to reduce a power consumption without degrading a communication quality of a packet transfer device. One or more of a receiver, a switch unit, and a transmitter include a QoS control circuit for applying QoS control to received packets. There is provided a power saving operation mode that enables power saving operation by changing a grain size of the QoS control according to a flow rate of the packets, and controlling whether or not to supply an electric power to the QoS control circuit or a part of the QoS control circuit, according to the flow rate of the packets.

Abstract: A relay device of relaying a communication packet is disclosed, which comprises: an input module configured to receive the communication packet as an input; a buffer configured to have a plurality of queues and temporarily accumulated the received communication packet; a sorter configured to sort the received communication packet to one of the plurality of queues, depending on a specific value obtained by a predetermined function that gives an aggregate output from an input which is transfer information regarding transfer of the communication packet; and a band controller configured to control a bandwidth for each of the plurality of queues and output communication packets accumulated in the plurality of queues for transmission of the communication packets. This ensures the quality of service, while saving the capacity of the buffer used for the queues.

Abstract: A packet forwarding device with a shaping unit, which is provided with queues for storing high priority packets and queues for storing low priority packets. The shaping unit transmits a packet read out from the non priority queue by giving a high priority when no transmit-wait packet exist in the priority queue even though the time to transmit a packet from the priority queue is reached.

Abstract: In order to allow priority transfer (fluctuation) over VLL packets while keeping each contracted bandwidth constantly, a leaky bucket model is expanded to have a threshold 1509 for permitting transmission of a packet (e.g. a WFQ packet) other than an LLQ packet and a threshold 1501 (larger than the threshold 1509) for permitting transmission of the LLQ packet (two-threshold leaky bucket model). In this manner, even when a WFQ cannot be transmitted, an LLQ can be transmitted with priority. In addition, while the total bandwidth of the WFQ and LLQ, i.e. the bandwidth of the VLL contains fluctuation, the contracted bandwidth can be complied with. The circuit of the model is provided in LLQ and WFQ transmission appointed time calculating circuits so as to calculate respective transmission appointed times so that an LLQ/WFQ is selected and a packet is selected based on the times considering priority.

Abstract: A packet information extraction circuit derives predetermined key information (for example, destination information or transmission source information) from a received packet. A HASH result computation circuit generates m (a plurality of) pseudo-random numbers (HASH results) of fixed length from the derived information. A cache table holds the key information and cumulative packet lengths within a predetermined time period by using the generated pseudo-random numbers as addresses. When a threshold value holding and comparing circuit senses that the cumulative packet length has exceeded a value held therein, it sends a notification signal to judgment means disposed in a packet exchange system. The key information items and the cumulative values of the packet lengths are stored in the cache table on the basis of the received packets in such a way that larger cumulative packet lengths are left behind, whereas smaller cumulative packet lengths are erased.

Abstract: A network management/apparatus connected to a plurality of packet relay apparatuses constituting a group through a network includes an energy saving level calculation unit for calculating an energy saving level of each of the packet relay apparatuses on the basis of a CPU usage ratio of the packet relay apparatus managed or a difference between the present energy saving level and the energy saving level of minimum guarantee of the packet relay apparatus, and an energy saving function setting unit for setting an energy saving function of the packet relay apparatuses on the basis of the energy saving level calculated by the energy saving level calculation unit.

Abstract: A packet communication system of the present invention has first mode, second mode and third mode to apply to input packets. The first mode is a mode that decides priority of the packet by at least one of the address information and the application information, the second mode is a mode that decides priority of the packet by the DS value, the third mode is a mode that decides rewrite the DS value by at least one of the address information and the application information. A control unit of the packet communication system switches a mode to apply an input packet of the first mode, the second mode and the third mode based on the packet header information of the input packet.

Abstract: An input interface segments a variable length packet into plurality of fixed length cells and generates an internal switching information based on the header information of the variable length packet. The input interface transmits the information to a switch and, after that, transmits the cells as the following cells of the information to the switch. The switch performs switching processing to the succeeding cells based on the information. Therefore, the information is not added to the cells. When an input interface starts to transmit cells generated from a packet to its destination output interface through the switch, the switch is reserved until all the cells arrive at the output interfaces.

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.