Nippon Telegraph and Telephone Corporation

Saki Hatta

Daisuke Kobayashi

Hiroyuki Uzawa

Shuhei Yoshida

Tomoaki Kawamura

Koyo Nitta

Satoshi Shigematsu

Nobuyuki Tanaka

Namiko Ikeda

Kenji Kawai

Ken Nakamura

Koji Yamazaki

Shoko Oteru

Junichi Kato

Takahiro Hatano

Shoko Ohteru

Naoki Miura

Yuki Arikawa

Yuta Ukon

Yuya Omori

Yusuke Sekihara

A packet capture device a packet analysis unit that analyzes an input packet; a flow identification unit that identifies a flow as a capture target; an output adjustment unit that adjusts a packet amount of the flow as the capture target to be output to a storage unit; a buffer unit that temporarily accumulates a packet of the flow as the capture target; and the storage unit that stores the packet of the flow as the capture target, in which the output adjustment unit is configured to decide whether to output the packet of the flow as the capture target to the storage unit for each predetermined measurement interval on the basis of a measurement result of the packet amount of the capture target in a predetermined measurement interval, and discard the packet not to be output to the storage unit.

Packet capture device and packet capture method

A traffic monitoring device includes an identification unit that identifies a flow of a packet received from a monitoring target network into a flow of a first flow group and a second flow group other than the first flow group on the basis of a rule table in which a predetermined rule is registered, a traffic aggregation unit that aggregates a traffic amount of the first flow group for each flow, an occurrence probability calculation unit that calculates an occurrence probability of each flow on the basis of a result of sampling at least some of the flow of the packet received, and a traffic estimation unit that estimates a traffic amount of each flow of the second flow group by multiplying the occurrence probability of each flow by the total value of the traffic amount of the second flow group.

Traffic monitoring device and traffic monitoring method

A packet capture system for capturing packets flowing in a capture target network, and a plurality of stages of packet distribution devices for capturing packet of a specific flow are cascade-connected, packet distribution devices identify a capture target flow by analyzing inputted packets, packet distribution devices other than a last-stage packet distribution device are configured to distribute packets to capture packets of a flow to be captured and output packets of a flow not to be captured to a next-stage packet distribution device, and the last-stage packet distribution device is configured to filter the packets of the flow to be captured and to discard the packets of the flow not to be captured.

Packet capture system, method and program

An embodiment is a packet capture device including a first local timer synchronized with an external global timer, a second local timer, a time stamp assign unit for assigning a time stamp to a inputted packet signal based on the second local timer, a filter unit for selecting the packet signal to which the time stamp is assigned, a capture file generation unit for receiving the selected packet signal, and a storage unit for storing a capture file generated in the capture file generation unit, wherein the capture file generation unit calculate a difference between a timer value of the first local timer and a timer value of the second local timer to correct the time stamp value on the basis of the difference.

Packet capture device, time stamp amendment method, packet capture method and packet capture program

A network load balancing apparatus has a data buffer for each communication path of a received packet's transfer destinations, calculates a first hash value using a field value contained in the packet, determines, based on the field value of the packet or the first hash value, a communication path of a transfer destination of the packet subject to external transfer control for transmission to a predetermined external server, determines, based on the first hash value, a communication path of a transfer destination of the packet to be subject to priority control, determines, based on a second hash value based on the first hash value, a communication path of a transfer destination of the packet to be subject to load balancing control, to match a preset load balancing situation of the data buffer, and transmits the packet to a data buffer corresponding to the communication path of the transfer destination.

Network load dispersion device and method

A network load balancing apparatus has a data buffer provided to each communication path of transfer destinations of a received packet and being associated with a virtual function, determines a destination virtual function based on a field value of the received packet, determines a communication path of a transfer destination of a packet to be subject to priority control based on a first hash value calculated using the field value, determines a communication path of a transfer destination of a packet to be subject to load balancing control, to match a preset load balancing situation of the data buffer, based on a second hash value based on the first hash value, and transmits the packet to a data buffer corresponding to the destination virtual function and the communication path of the transfer destination.

Network load distribution device and method

A packet processing apparatus includes a line adapter configured to receive packets from a communication line, a packet combining unit configured to generate a combined packet by combining a plurality of packets received from the communication line, a packet memory configured to store packets received from the communication line, and a combined packet transferring unit configured to DMA transfer the combined packet generated by the packet combining unit to the packet memory. The combined packet transferring unit determines an address of start data of each packet inside the combined packet on the packet memory, writes information on the address into the descriptor that is a predetermined data area on a memory, and DMA transfers the combined packet to the packet memory.

Packet processing device and packet processing method

A link control circuit () includes a plurality of hardware processing units serving as an uplink parser unit () configured to output, as an event, the contents of link control notified by an uplink control frame, a timer unit () configured to start/stop a timer and output a link event in accordance with expiration of the timer, a frame generation unit () configured to generate a downlink control frame containing the contents of link control, and a state management unit () configured to manage the state of the link in accordance with these events, and instruct the timer unit to start/stop the timer and the frame generation unit to generate the downlink control frame in accordance with the state of the link, thereby controlling connection establishment, maintenance, and disconnection of the link. Each of the hardware processing units includes a memory configured to store an externally changeable internal program describing a corresponding processing operation, and a processor configured to execute the corresponding processing operation in accordance with the internal program.

Link control circuit

An upstream allocation circuit () and a downstream allocation circuit () are provided in an OLT (). For example, a superimposed frame obtained by bundling upstream frames (upstream control frames+upstream data frames) from all ONUS is input to the upstream allocation circuit () via a frame reproduction circuit (-). The superimposed frame may be generated at the stage of optical signals or generated after converting optical signals into electrical signals. The upstream allocation circuit () allocates each of the upstream control frames bundled into the superimposed frame to a predetermined PON control circuit () based on information (PON port number or LLID) added to the frames. The downstream allocation circuit () allocates, to a preset frame reproduction circuit (), each downstream control frames output from the PON control circuits ().

Station-side apparatus in optical transmission system and optical transmission system

A selection and distribution circuit () is provided between N optical transceivers () and one PON control circuit (). The selection and distribution circuit () selects the optical transceiver () corresponding to an upstream frame that time-divisionally arrives, thereby transferring the upstream frame opto-electrically converted by the transceiver () to the PON control circuit () and distributing a downstream frame from the PON control circuit () to each optical transceiver (). A power supply control circuit () stops power supply to at least one of one of optical transceivers () that are not used to transfer the frame of the optical transceivers () and a circuit that is not used to transfer the frame in the selection and distribution circuit (). This can reduce the system cost per ONU in the optical transmission system.

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Tokyo, Japan

Saki Hatta