Nippon Telegraph and Telephone Corporation

Ntt Corporation

Takamitsu Tochino

Tomoya Hatano

Hirotaka Nakamura

Hirotaka Ujikawa

Takashi Mitsui

Kota Asaka

Yoshihito Sakai

Tatsuya Shimada

Keita Takahashi

A signal transfer device according to an embodiment receives a plurality of signals including an aperiodic signal having a higher priority than other signals, respectively holds the plurality of received signals by a plurality of buffers according to the priority, acquires signal information including at least one of a time at which the aperiodic signal is transmitted or received and a data length of the aperiodic signal, predicts a timing at which the aperiodic signal arrives at the buffer based on the acquired signal information, sets reservation of a period for transmitting the aperiodic signal with priority over other signals based on the predicted timing, controls the plurality of buffers to output the aperiodic signal with priority over other signals in the period in which the reservation is set, and transmits the signal output by the buffer.

Signal transfer device, signal transfer method, signal transfer program, and signal transfer system

There is provided a communication method used in a communication system in which a plurality of communication apparatuses is connected by an optical ring network, the communication method including: setting one of the plurality of communication apparatuses as a master communication apparatus and the other communication apparatuses as slave communication apparatuses, causing the master communication apparatus to transmit an optical signal at transmission timing determined in the master communication apparatus; causing the master communication apparatus to transmit an assignment signal for assigning, to the slave communication apparatuses, transmission timing at which an optical signal on at least one wavelength is time-division multiplexed and transmitted; and causing the slave communication apparatuses to transmit an optical signal to the optical ring network based on transmission timing assigned by the assignment signal received from the master communication apparatus. As a result, the number of wavelengths needed for communication is reduced, and even when communication paths increases due to an increase in the number of optical transmission apparatuses, there is no need to increase the number of wavelengths, thereby solving the problem in economic efficiency.

Communication control device, communication method, communication system and communication program

A communication device is connected to a wavelength-multiplexed optical ring network, and performs communication by performing time-division multiplexing on optical signals at each wavelength. In a case where a control signal transmitted from the master communication device is not received in a predetermined period, the communication device instructs a scheduler unit to suspend transmission of data at a failure wavelength that is the wavelength at which the host communication device has been determined not to be operating properly, also instructs the scheduler unit to transmit the data stored in the buffer of the failure wavelength at another wavelength, and suspends allocation of new data to the buffer of the failure wavelength. Thus, the delay in transmission of data at the failure wavelength can be shortened.

Communication device, communication method, communication system and communication program

A communication device including a first communication device and a plurality of second communication devices in an optical access system in which a first communication device and the plurality of second communication devices perform communications with each other under a time division multiple access scheme includes an Ethernet controller configured to implement the communications as Ethernet (registered trademark) communications, and a link failure processing unit configured to output, in response to reception of a link failure notification for notifying occurrence of a link failure in the communications from the first communication device, a termination instruction to terminate data transmission when the communication device is performing the data transmission to the first communication device, and a start instruction to start the data transmission after recovery from the link failure when the communication device is not performing the data transmission to the first communication device.

Communication apparatus and communication method

Transmitting devices used in an optical access system in which a plurality of the transmitting devices transmit an optical burst signal to a receiving device by time division multiple access, the transmitting devices each including an arithmetic processing unit, the arithmetic processing unit including: a data signal transmission instruction unit, the a data signal transmission instruction unit that outputs a first instruction for controlling transmission processing of a data signal on the basis of a requester's instruction; an optical signal control instruction unit that outputs a second instruction for controlling output processing of an optical signal on the basis of the requester's instruction; and an instruction output adjustment unit that adjusts a timing at which the first instruction is output and a timing at which the second instruction is output.

Growing community of inventors

Musashino, Japan

Takamitsu Tochino