Abstract: A storage switch with bandwidth control function for preventing discarding of packets for bandwidth breach when sending or receiving storage data using an iSCSI protocol on a wide area network having a covenant (guaranteed) bandwidth, when the quantity of storage data traffic sent by the initiator or target was judged a bandwidth breach or violation. The traffic amount is predicted from the Expected Data Transfer Length contained in the read request of the iSCSI command and the Desired Data Transfer Length contained in the R2T command, when that command is sent to the target and the initiator and the bandwidth is regulated by controlling the transmission timing of that command.

Abstract: A data transfer apparatus is provided for monitoring the bandwidth of a first and a second flow, comprises flow detecting means for comparing information in a header field of a packet with the first and second detection conditions to detect a flow to which the packet belongs, compliance/violation determining means for measuring the bandwidth of the packet belonging to the detected flow to determine whether the packet complies with or violates a traffic condition which is set corresponding to each flow detection condition, and packet processing determining means for determining processing for a packet which satisfies both the first and second flow conditions based on the compliance/violation determination results corresponding to both traffic conditions, and determining processing for a packet which satisfies one of the first and second flow conditions based on the compliance/violation result corresponding to the flow detection condition satisfied by the packet.

Abstract: A packet transfer apparatus having: a flow detector 30 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.

Abstract: A high quality network is provided by not generating a sorting time when registering look-up conditions in a content addressable memory, and the physical banks activated during look-up of the look-up conditions are limited.

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 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 of the flow bundle identifier received from the flow detector and performing a predetermined computing process.

Abstract: To control a bandwidth without the need for a large-capacity buffer. This invention provides a packet transfer apparatus connected to first device and second device, with a network therebetween, including: an input unit that receives a packet from the first device; a packet storage unit that stores the packet; a packet processing unit that stores the packet in the packet storage unit; a packet checking unit that checks whether the packet is related to data request; a packet analyzing unit that analyzes the amount of data requested by the data request; a transfer control unit that controls transfer of the packet on the basis of the analyzed amount of data; and an output unit that sends the received packet to the second device.

Abstract: A header processing unit includes a key information supply unit that manages MAC addresses and MAC key information having a short bit length that corresponds to the addresses, and decides key information corresponding to a source MAC address and a destination MAC address of an input frame. A destination decision unit performs destination decision processing based on corresponding key information instead of destination MAC addresses. A flow decision unit decides a flow based on key information corresponding to a destination MAC address and a source MAC address. Since the key information supply unit does not need to set plural identical MAC addresses, the header processing unit becomes inexpensive. Thus, this invention achieves an inexpensive switch that performs output decision processing and flow decision processing.

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: There is provided a packet forwarding device which always carries out high-speed search in a routing table by using a TCAM. The device includes a CAM (120) which includes a first CAM entry (120-1) to set high order bits of destination address conditions and a second CAM entry (120-2) to set low order bits of the destination address conditions, a first search unit which compares high order bits of a destination address of an input packet with the first CAM entry to search for a matching destination address condition, and a second search unit which compares low order bits of the destination address of the packet with the second CAM entry to search for a matching destination address condition when no destination address condition corresponding to the high order bits of the destination address of the packet is uniquely decided based on a result of the search.

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: 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 storage switch with bandwidth control function for preventing discarding of packets for bandwidth breach when sending or receiving storage data using an iSCSI protocol on a wide area network having a covenant (guaranteed) bandwidth, when the quantity of storage data traffic sent by the initiator or target was judged a bandwidth breach or violation. The traffic amount is predicted from the Expected Data Transfer Length contained in the read request of the iSCSI command and the Desired Data Transfer Length contained in the R2T command, when that command is sent to the target and the initiator and the bandwidth is regulated by controlling the transmission timing of that command.

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 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: Cells are discarded in conformity with the order of priority when congestion occurs by discarding cells of a traffic class without any special contract for a transfer rate at the time of setting up a connection. A node stores priority information concerning cell discard corresponding to a connection identifier and controls the cell discard in accordance with the discard condition determined by the accumulated number of cells for each connection in the node and cell 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 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 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.