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: 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 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: In a device that interworks a VLAN network and an MPLS network, a VLAN ID is associated with an MPLS label. In a device that performs interworking from a VLAN network to an MPLS network, an output MPLS label is determined from a pair of a VLAN ID and the information in the layer 3 or layer 4 header of a packet. The output MPLS label is assigned an independent value for each VLAN. In a device that performs interworking from the MPLS network to another VLAN network, the input MPLS label is associated with a VLAN ID.

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 packet switch for switching variable length packets, where each output port interface 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 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 and a packet read-out controller for reading out 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 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 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: 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 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: 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 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: 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: 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: 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 packet forwarding apparatus provided with a plurality of line interface units, comprises a routing processing unit for referring to a routing table, based on header information of received packet to specify one of output lines to output the received packet, a flow detection unit for referring to an entry table, in which a plurality of entries with flow conditions and control information are registered, to retrieve control information defined by the entry with a flow condition which coincides with that of the header information of the received packet, and a packet forwarding unit for transferring the received packet to one of the line interface units connected to the output line specified by the routing processing unit.

Abstract: In one embodiment, a bandwidth monitoring device comprises a packet receiving circuit configured to receive packets; a counter configured to count a total packet length by adding up inputted packet lengths including a packet length of a next input packet and subtracting outputted packet lengths to produce a counted value; a timer configured to time a packet receiving time; a memory configured to store a number of packet receiving times and a number of counted values counted by the counter which correspond to the packet receiving times, respectively; a counter rate-of-change calculating portion configured to calculate a change rate by a first counted value corresponding to an oldest packet receiving time stored in the memory representing an oldest time at which a packet was received and a second counted value corresponding to a latest packet receiving time stored in the memory representing a latest time at which a packet was received; and a determining portion configured to decide whether the next input packet

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 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.