Abstract: 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.

Abstract: Time taken for resuming communication in a protection scheme using a backup path in an optical communication system including a master station device and a plurality of slave station devices is decreased. The plurality of slave station devices are connected in parallel to a looped path. A communication path between the master station device and each of the slave station device includes a normal path and a backup path. The master station device performs communication control processing for each of the slave station device based on RTT. A first slave station device is a slave station device with which communication through the normal path has become impossible. First backup path RTT of the first slave station device is calculated based on first normal path RTT of the first slave station device, first partial RTT between the master station device and the looped path, and loop propagation time necessary for one trip through the looped path.

Abstract: A wavelength multiplexing communication system includes a master station apparatus and a plurality of slave station apparatuses. The master station apparatus includes a wavelength multiplexing communication unit that performs wavelength multiplexing communication with the plurality of slave station apparatuses by wavelengths the number of which is equal to or less than the number of the plurality of slave station apparatuses using an optical signal of a wavelength in a first wavelength group and an optical signal of a wavelength in a second wavelength group.

Abstract: The present invention enables shortening the time required for resuming communication in a protection method that uses a backup path in an optical communication system that includes a master station device and multiple slave station devices. The slave station devices are connected to a loop path in parallel. The communication paths between the master station device and the slave station devices include a normal path and a backup path. The master station device executes communication control processing with respect to the slave station devices based on the RTTs. A first slave station device is one of the slave station devices, and a second slave station device is a slave station device that cannot perform communication via the normal path.

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.

Abstract: The present invention enables shortening the time required for resuming communication in a protection method that uses a backup path in an optical communication system that includes a master station device and multiple slave station devices. The slave station devices are connected to a loop path in parallel. The communication paths between the master station device and the slave station devices include a normal path and a backup path. First and second slave station devices are slave station devices that cannot perform communication via the normal path. The magnitude relationship between backup path RTTs is opposite to the magnitude relationship between normal path RTTs. If the second normal path RTT for the second slave station device is longer than the first normal path RTT for the first slave station device, the first backup path RTT is longer than the second backup path RTT, and the second backup path RTT is shorter than the first backup path RTT.

Abstract: A base station which performs relaying between a wireless terminal and a server, the wireless terminal and the server establishing connection with each other, includes a request detection unit which detects a connection establishment request transmitted to the server by the wireless terminal, a response detection unit which detects an acknowledgment transmitted to the wireless terminal by the server on the basis of the connection establishment request detected by the request detection unit, and a band allocation unit which, if the response detection unit detects the acknowledgment, performs allocation so as to expand a band over which the wireless terminal is capable of transmission to the server, regardless of presence or absence of a buffer amount notification from the wireless terminal.

Abstract: An optical transmission device which performs relaying between a terminal device and a server via an optical network device, the terminal device and the server establishing connection with each other, includes a request detection unit which detects a connection establishment request transmitted to the server by the optical network device on the basis of a connection establishment request transmitted to the server by the terminal device, a response detection unit which detects an acknowledgment transmitted to the terminal device by the server on the basis of the connection establishment request detected by the request detection unit, and a band allocation unit which, if the response detection unit detects the acknowledgment, performs allocation so as to expand a band over which the optical network device is capable of transmission to the server, regardless of presence or absence of a buffer amount notification to be transmitted by the optical network device.

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 larger than a preset value, transmits a command that sets the client to enlarge a congestion window to a predetermined value, regardless of presence or absence of an acknowledgement sent by the server.

Abstract: A wavelength multiplexing communication system includes a master station apparatus and a plurality of slave station apparatuses. The master station apparatus includes a wavelength multiplexing communication unit. The wavelength multiplexing communication unit performs wavelength multiplexing communication with the plurality of slave station apparatuses by using optical signals having the number of wavelengths equal to or less than the number of the plurality of slave station apparatuses. The slave station apparatus includes an optical communication unit. When the main signal communication is performed in the host slave station apparatus, the optical communication unit communicates with the master station apparatus by an optical signal having the same wavelength as a wavelength used by another slave station apparatus in which a main signal notification is not performed.

Abstract: In an optical communication system, an optical communication device and a plurality of optical transmission devices are loop-connected via transmission line. An optical signal transmission unit of the optical communication device, when no communication interruption occurs in the transmission line, outputs an optical signal addressed to a communication destination device being another optical communication device that communicates with the own device to a transmission line connected to either one of two neighboring optical transmission devices. The optical signal transmission unit outputs, at the time of communication interruption occurring in the transmission line, an optical signal addressed to the communication destination device to both of transmission lines connected to respective two neighboring optical transmission devices.

Abstract: A bandwidth allocation apparatus includes an acquisition unit acquiring scheduling information related to transmission of uplink data from a first subscriber line termination apparatus corresponding to a subscriber line termination apparatus needing to transfer uplink data with low latency, a requested amount reception unit receiving, from second subscriber line termination apparatus corresponding to a subscriber line termination apparatus not needing to transfer uplink data with low latency, information representing a requested amount related to transmission of uplink data from the second subscriber line termination apparatus, in a requested amount reception cycle corresponding to a cycle equal to or longer than a predetermined maximum round-trip time, and an allocation unit allocating, in an allocation amount determination cycle shorter than the requested amount reception cycle, a bandwidth to the uplink data from the first subscriber line termination apparatus on a basis of the scheduling information, and

Abstract: A transfer apparatus include a distribution unit, a storage unit, and a transfer unit, in which the distribution unit is configured to identify a plurality of networks to which frames belong, distribute the frames for each of the networks based on an identification result, and store the distributed frames in the storage unit, the storage unit is configured to store information of a time at which a frame of the frames is stored in the storage unit and the frame in association with each other, and the transfer unit is configured to detect a period of time for which the frame stays in the storage unit, detect a remaining period to send which is a remaining time of a time for which the frame is permitted to stay in the storage unit, for each of the frames, based on a difference between the time for which the frame stays in the storage unit and the delay upper limit value, and output the frame to a predetermined apparatus based on the remaining period to send.

Abstract: A signal forwarding system includes: a plurality of signal forwarding devices forming a plurality of communication routes between a slave station and a master station; and a route control device that determines a communication route, wherein the route control device includes at least: a communication route calculation unit that calculates a communication route in response to a route switching request; and a forward destination setting instruction unit that outputs forward destination setting information based on the communication route, the signal forwarding devices include at least: a forward destination setting instruction acquisition unit that acquires the forward destination setting information; a forward destination set unit that changes a forward destination based on the forward destination setting information; and a forward unit that outputs input traffic based on the forward destination, and any of the route control device and the signal forwarding devices includes: a traffic monitor unit; a non-signa

Abstract: A communication processing device including: a memory that stores data relating to a pre-update firmware, and second data relating to a post-update firmware, and that stores first reference destination address indicating the storage area of reference destination included in the first data in association with the reference destination; a rewriting unit configured to rewrite at least some of the first reference destination address stored in the memory with second reference destination address indicating the storage area of the reference destination in the second data; and a control unit configured to, when referring to the reference destination in the first data, refer to the second data on the basis of the second reference destination address stored in the memory.

Abstract: A communication system includes a first processor that performs processing for transmitting a signal to and receiving a signal from a communication destination device and a second processor that performs processing of an additional function. The second processor includes a decoding unit that decodes a transmission signal encoded by the first processor or a reception signal encoded by the communication destination device, an information acquiring unit that acquires information from the transmission signal or the reception signal decoded by the decoding unit, an additional function executing unit that performs the processing of the additional function using the information acquired by the information acquiring unit, and an encoding unit that performs processing for encoding the decoded transmission signal and outputting a resulting signal to the communication destination device or processing for encoding the decoded reception signal and outputting a resulting signal to the first processor.

Abstract: A communication system includes a subscriber network unit and a communication device provided in an accommodating station. The subscriber network unit includes an acquisition unit that acquires uplink data from one or more lower-layer devices. The communication device includes: a data processing unit that acquires the uplink data from the subscriber network unit using a band of uplink communication and executes data processing on the acquired uplink data; a policy determination unit that determines a policy of band allocation of the uplink communication on the basis of the result of the data processing; and an allocation control unit that allocates the band of the uplink communication to the subscriber network unit on the basis of the policy.

Abstract: A transfer apparatus include a distribution unit, a storage unit, and a transfer unit, in which the distribution unit is configured to identify a plurality of networks to which frames belong, distribute the frames for each of the networks based on an identification result, and store the distributed frames in the storage unit, the storage unit is configured to store information of a time at which a frame of the frames is stored in the storage unit and the frame in association with each other, and the transfer unit is configured to detect a period of time for which the frame stays in the storage unit, detect a remaining period to send which is a remaining time of a time for which the frame is permitted to stay in the storage unit, for each of the frames, based on a difference between the time for which the frame stays in the storage unit and the delay upper limit value, and output the frame to a predetermined apparatus based on the remaining period to send.

Abstract: A virtual subscriber line terminal station device includes a software component including software to be added in accordance with a service requirement; and hardware having general-purpose functions; wherein the hardware includes a communication unit that receives a bandwidth allocation request transmitted by a subscriber line termination device; and the software component includes a bandwidth allocation component. The bandwidth allocation component has an individual unit that, based on an algorithm for allocating bands, computes a bandwidth to be allocated to the subscriber line termination device that transmitted the bandwidth allocation request; a common unit that, in accordance with the bandwidth allocated by the individual unit, allocates the bandwidth to the subscriber line termination device; and an interface between the individual unit and the common unit. The common unit converts the bandwidth allocation request received by the communication unit to a format that can be used by the individual unit.

Abstract: A virtual subscriber line terminal station device includes a software component including software to be added in accordance with a service requirement; and hardware having general-purpose functions; wherein the hardware includes a communication unit that receives a bandwidth allocation request transmitted by a subscriber line termination device; and the software component includes a bandwidth allocation component. The bandwidth allocation component has an individual unit that, based on an algorithm for allocating bands, computes a bandwidth to be allocated to the subscriber line termination device that transmitted the bandwidth allocation request; a common unit that, in accordance with the bandwidth allocated by the individual unit, allocates the bandwidth to the subscriber line termination device; and an interface between the individual unit and the common unit. The common unit converts the bandwidth allocation request received by the communication unit to a format that can be used by the individual unit.