公开(公告)号：US20230145000A1

公开(公告)日：2023-05-11

申请号：US17914849

申请日：2020-03-30

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Naotaka SHIBATA ,  Hirotaka UJIKAWA

IPC: H04W24/08 ,  H04W76/10 ,  H04W40/12

CPC classification number: H04W24/08 ,  H04W76/10 ,  H04W40/12 ,  H04W80/06

Abstract: A monitoring device that monitors a network to which a plurality of terminal devices establishing a connection based on TCP are connected, includes: a request detection unit that detects a connection establishment request that a terminal device becoming a client sends to another terminal device becoming a server; an available bandwidth calculation unit that calculates an available bandwidth by subtracting a current amount of traffic from an allowable communication capacity, for each communication path identified by the connection establishment request detected by the request detection unit; and a setting command unit that, when the available bandwidth calculated by the available bandwidth calculation unit is smaller than a congestion window, transmits a command that sets the client to lower a slow start threshold to a predetermined value, or a command that sets the server to lower a window size to a predetermined value, regardless of whether or not a timeout occurs.

公开(公告)号：US20220294742A1

公开(公告)日：2022-09-15

申请号：US17634197

申请日：2019-08-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Naotaka SHIBATA ,  Hiroyuki UZAWA ,  Jun TERADA

IPC: H04L47/283 ,  H04L47/24 ,  H04L47/62 ,  H04L49/20 ,  H04L45/24

Abstract: A path control device controls a plurality of paths for transmitting signals through a network including a plurality of signal transfer devices that transfer signals while switching a first transmission period during which high-priority traffic can be transmitted and a second transmission period during which low-priority traffic can be transmitted. The path control device includes: a calculation unit that calculates a plurality of paths through which signals are transferred, based on network configuration information indicating a configuration of the network; an estimation unit that estimates paths for low-priority traffic so as to increase the number of low-priority traffic flows to be transferred during a predetermined period through the plurality of paths calculated by the calculation unit, in a case in which the plurality of signal transfer devices detect an end of high priority traffic in the first transmission period, in accordance with statistical values in the second transmission period based on a transmission schedule made to change the first transmission period after the end of high-priority traffic to the second transmission period; and a determination unit that determines, for each of the plurality of signal transfer devices, output destination setting information such that the paths estimated by the estimation unit are set to an output destination of low-priority traffic.

公开(公告)号：US20220263762A1

公开(公告)日：2022-08-18

申请号：US17595918

申请日：2019-06-03

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Naotaka SHIBATA ,  Hiroyuki UZAWA ,  Noriyuki OTA ,  Jun TERADA

IPC: H04L47/22 ,  H04L49/90 ,  H04L43/0888

Abstract: A buffer unit including a plurality of buffers, a sorting unit configured to sort an input signal to any of the plurality of buffers based on header information, a rate calculation unit configured to calculate a rate at which the input signal is read from each of the plurality of buffers based on burst information of the input signal, an adjustment unit configured to adjust a rate at which the input signal is read from each of the plurality of buffers based on the rate calculated by the rate calculation unit, and a transfer unit configured to transfer the signal read from each of the plurality of buffers are provided.

公开(公告)号：US20220200911A1

公开(公告)日：2022-06-23

申请号：US17595063

申请日：2020-04-27

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hiroyuki UZAWA ,  Naotaka SHIBATA ,  Yoichi FUKADA ,  Jun TERADA

IPC: H04L47/22 ,  H04L49/351 ,  H04L47/32

Abstract: A communication control system includes a plurality of layer 2 switches (SWs); and a communication control device that controls communication of the SWs. Each SW includes one or more queues that each have a variable queue length for accumulating input frames, and a transmission unit that has a shaping function of transmitting the frames accumulated in the queues to a desired destination at a desired rate. The communication control device includes a correction processing unit that acquires an amount of discarded data generated in each queue of the SW, and multiplies the acquired amount of discarded data by a correction coefficient weighted by the cumulative number of times of discarding occurrences for which the amount of discarded data is not 0 to obtain a corrected amount of discarded data; and an adjustment processing unit that determines adjustment values for the queue length of each queue and shaping rate of the SW based on the corrected amount of discarded data, and notifies each SW of the adjustment values.

公开(公告)号：US20180234188A1

公开(公告)日：2018-08-16

申请号：US15580799

申请日：2016-06-16

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Daisuke HISANO ,  Jun TERADA ,  Naotaka SHIBATA ,  Shigeru KUWANO

IPC: H04B10/29 ,  H04J14/02 ,  H04B10/2575 ,  H04L5/14 ,  H04J14/08 ,  H04B10/27

CPC classification number: H04B10/29 ,  H04B10/2575 ,  H04B10/27 ,  H04J3/16 ,  H04J14/02 ,  H04J14/08 ,  H04L5/14

Abstract: A transmission system for relaying communication of communication systems includes a relay unit configured to relay uplink communication and downlink communication of a communication system that performs a time division duplex (TDD) mode through signals of different wavelengths, an information acquisition unit configured to acquire time division information indicating timings of the uplink communication and the downlink communication in the communication system that performs the TDD mode, a calculation unit configured to calculate a free period unused in relaying of communication of the communication system that performs the TDD mode on the basis of the time division information for each wavelength, and an instruction unit configured to instruct the relay unit to relay communication of another communication system different from the communication system that performs the TDD mode in the free period for each wavelength calculated by the calculation unit.

公开(公告)号：US20180138979A1

公开(公告)日：2018-05-17

申请号：US15572636

申请日：2016-04-06

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Naotaka SHIBATA ,  Shigeru KUWANO ,  Yutaka KAMAMOTO ,  Takehiro MORIYA ,  Jun TERADA

IPC: H04B10/2575 ,  H04L27/26

CPC classification number: H04B10/2575 ,  H03M7/30 ,  H03M7/3073 ,  H03M7/4031 ,  H04J11/00 ,  H04L27/2628

Abstract: An optical communication system includes a signal processing apparatus and a wireless apparatus between which functions of a base station are divided, wherein a periodic symbol sequence including a cyclic prefix appended to a signal of a predetermined size to which an IFFT (Inverse Fast Fourier Transform) has been applied is transmitted between the signal processing apparatus and the wireless apparatus by means of digital RoF (Radio over Fiber) transmission, the signal processing apparatus and the wireless apparatus each include a transmission unit and a reception unit, the transmission unit includes: a first separation unit that acquires symbol information relating to a starting position of the symbol sequence and lengths of symbols constituting the symbol sequence, and that equalizes the lengths of the symbols by separating a portion of the symbol sequence based on the acquired symbol information; and a compression unit that compresses symbols that are to be compressed from which the separated portion of the symbol sequence has been removed, and the reception unit includes an expansion unit that expands the compressed symbols and restores the symbols.

公开(公告)号：US20250141552A1

公开(公告)日：2025-05-01

申请号：US18691300

申请日：2021-09-17

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Naotaka SHIBATA ,  Shin KANEKO

IPC: H04B10/27 ,  H04J14/02 ,  H04Q11/00

Abstract: An optical transmission device includes a wavelength cross connection unit that receives an optical signal transmitted from a first optical transmission device, separates the input optical signal according to a wavelength, and outputs each of the separated optical signals from a port corresponding to the wavelength, and an optical switch that outputs an optical signal output from the wavelength cross connection unit from a port to which a destination subscriber device is connected, in which the wavelength cross connection unit outputs the optical signal toward the optical switch in a case where the optical signal is an optical signal addressed to a subscriber device connected under control of a host device, and outputs the optical signal toward a second optical transmission device different from the first optical transmission device in a case where the optical signal is not an optical signal addressed to a subscriber device connected under control of the host device.

公开(公告)号：US20250016481A1

公开(公告)日：2025-01-09

申请号：US18710996

申请日：2021-11-25

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Naotaka SHIBATA ,  Shin KANEKO ,  Takuya KANAI

IPC: H04Q11/00 ,  H04B10/27

Abstract: An optical communication system including an optical switch that is connected to a plurality of optical transmission lines and outputs an optical signal input from any of the optical transmission lines to another optical transmission line, and a transfer unit configured to convert simplex transmission into duplex transmission or converts duplex transmission into simplex transmission between a subscriber device and the optical switch or between a first port of the optical switch to which the subscriber device is directly or indirectly connected and a second port opposite to the first port, and transfers the optical signal so as not to cause interference between uplink and downlink.

公开(公告)号：US20250007610A1

公开(公告)日：2025-01-02

申请号：US18709730

申请日：2021-11-18

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Shin KANEKO ,  Takuya KANAI ,  Naotaka SHIBATA ,  Junichi KANI

IPC: H04B10/27 ,  H04B10/294

Abstract: An optical communication system including a subscriber device that performs optical connection with other subscriber device by End-End, and a management control device that controls each subscriber device, wherein the subscriber device includes an optical signal transmission unit configured to transmit an optical signal, an optical signal reception unit configured to receive an optical signal transmitted from the other subscriber device, and an output function unit configured to output an optical signal outputted by the optical signal transmission unit to an optical transmission line regardless of a wavelength and outputs an optical signal inputted from the optical transmission line to the optical signal reception unit regardless of the wavelength, and the management control device allocates wavelengths so that a transmission wavelength of the subscriber device becomes a reception wavelength of the other subscriber device and a transmission wavelength of the other subscriber device becomes a reception wavelength of the subscriber device.

公开(公告)号：US20240421904A1

公开(公告)日：2024-12-19

申请号：US18704126

申请日：2021-10-27

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takeshi IMAI ,  Naotaka SHIBATA ,  Shin KANEKO

IPC: H04B10/112 ,  H04B10/50

Abstract: An aspect of the present invention is a mobile including an optical transmitter that transmits an optical signal by irradiating a light receiver of a reception device with a beam, an instruction receiver that receives a movement instruction to move the mobile to a designated position, a position acquirer that acquires a current position of the mobile, a direction acquirer that acquires a moving direction from the current position to the designated position, and a beam controller that performs change control of changing an irradiation direction of a beam according to the moving direction within a range in which the beam is emitted to the light receiver before the mobile starts to move toward the designated position.