Abstract: In the elastic optical network, there has been the problem that processing steps increase that are required to re-optimize client signals to be concentrated; therefore, an optical network controller according to an exemplary aspect of the present invention includes reallocation detection means for monitoring an operation status of at least one of an optical communication channel and an optical node device that constitute an optical network, and determining, based on the operation status, whether or not to reallocate a client signal accommodated in an optical path set in the optical network; design-candidate exclusion means for designating, as a design exclusion object, at least one of the optical communication channel and the optical node device that are associated with an optical path targeted for reallocation that accommodates the client signal that the reallocation detection means has determined to reallocate; optical path design means for determining an alternative route for the optical path targeted for

Abstract: In an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid, it is difficult to improve the usage efficiency of an optical frequency band owing to the occurrence of fragmentation of the optical frequency band; therefore, an optical network controller according to an exemplary aspect of the present invention includes an optical frequency region setting means for dividing an optical frequency band used in an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid, and setting a plurality of optical frequency regions; and an optical path setting means for setting optical paths having a common attribute in at least one of the plurality of optical frequency regions.

Abstract: It is difficult to improve the usage efficiency of an optical communication network due to the passband narrowing effect in a wavelength selection process in an optical communication network using a wavelength division multiplexing system; therefore, an optical network management apparatus according to an exemplary aspect of the present invention includes wavelength selection information generating means for generating wavelength selection information on a wavelength selection process through which an optical path accommodating an information signal goes, with respect to each optical path; and wavelength selection information notifying means for notifying an optical node device through which the optical path goes of the wavelength selection information.

Abstract: In an optical communication network using the wavelength division multiplexing system, the accommodation efficiency for the optical paths decreases, and it becomes difficult to use the optical communication network efficiently, if the optical frequency slots are used concentrically in a specific optical fiber; therefore, an optical path design apparatus according to an exemplary aspect of the present invention includes route candidate selection means for searching for a route of an optical path to accommodate a communication demand and selecting a plurality of route candidates; optical path candidate selection means for selecting a plurality of optical path candidates by allocating an optical frequency band required to accommodate the optical path to each of optical fibers on the plurality of route candidates; and optical path determination means for determining the optical path from among the plurality of optical path candidates based on an optical frequency band utilization rate in the optical fibers.

Abstract: In an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid, it is difficult to improve the usage efficiency of an optical frequency band owing to the occurrence of fragmentation of the optical frequency band; therefore, an optical network controller according to an exemplary aspect of the present invention includes an optical frequency region setting means for setting a plurality of optical frequency regions in an optical frequency band used in an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid; an optical path setting means for setting optical paths having a common attribute in at least one of the plurality of optical frequency regions; and an optical frequency region control means for changing an optical frequency width of the optical frequency region, and instructing the optical frequency region setting means to reconfigure, as the plurality of optical frequency regions, a plurality of optical frequ

Abstract: It is difficult to improve the usage efficiency of an optical communication network due to the passband narrowing effect in a wavelength selection process in an optical communication network using a wavelength division multiplexing system; therefore, an optical network management apparatus according to an exemplary aspect of the present invention includes wavelength selection information generating means for generating wavelength selection information on a wavelength selection process through which an optical path accommodating an information signal goes, with respect to each optical path; and wavelength selection information notifying means for notifying an optical node device through which the optical path goes of the wavelength selection information.

Abstract: An optical network control device includes: a path setting unit that sets, based on topology information including a connection relationship among a plurality of nodes and a first route selection index value of routes each connecting the plurality of nodes, a first path for a route having the first route selection index value being minimum from among route candidates linking a start point node and an end point node of a requested traffic; a topology information modification unit that calculates a second route selection index value acquired by increasing the first route selection index value of the route that accommodates the first path; and a path selection unit that selects a second path for a route having the second route selection index value being minimum from among the route candidates.

Abstract: It is made possible to accommodate a plurality of services and transmit each of the accommodated services to a corresponding transmission device. An optical transmitter according to an exemplary aspect of the present invention includes sub-carrier adjusting means for outputting sub-carriers to a plurality of output ports according to a control signal; encoding processing means for mapping client data on a plurality of output lanes according to the control signal; a plurality of modulation means for modulating the sub-carriers inputted through the output ports by client data inputted through the output lanes and outputting modulated signals; and control means for generating and outputting the control signal based on transmission information.

Abstract: In an optical network system based on a wavelength division multiplexing system using a flexible frequency grid, with the diversification of optical modulation methods, the management burden on an optical network management device increases, and its control becomes complicated; therefore, an optical network system according to an exemplary aspect of the present invention includes an optical network management device configured to receive a traffic demand, design an optical path capable of accommodating the traffic demand, and create optical path design information of a design result; and an optical node device configured to be used for creating the optical path, wherein the optical node device calculates an allocable bandwidth from the optical path design information and optical node device information on a configuration of the optical node device, and the allocable bandwidth is an optical frequency bandwidth of a generable optical path that the optical node device is capable of generating, and the optical ne

Abstract: In the elastic optical network, there has been the problem that processing steps increase that are required to re-optimize client signals to be concentrated; therefore, an optical network controller according to an exemplary aspect of the present invention includes reallocation detection means for monitoring an operation status of at least one of an optical communication channel and an optical node device that constitute an optical network, and determining, based on the operation status, whether or not to reallocate a client signal accommodated in an optical path set in the optical network; design-candidate exclusion means for designating, as a design exclusion object, at least one of the optical communication channel and the optical node device that are associated with an optical path targeted for reallocation that accommodates the client signal that the reallocation detection means has determined to reallocate; optical path design means for determining an alternative route for the optical path targeted for

Abstract: It is difficult to improve the usage efficiency of an optical communication network due to the passband narrowing effect in a wavelength selection process in an optical communication network using a wavelength division multiplexing system; therefore, an optical network management apparatus according to an exemplary aspect of the present invention includes wavelength selection information generating means for generating wavelength selection information on a wavelength selection process through which an optical path accommodating an information signal goes, with respect to each optical path; and wavelength selection information notifying means for notifying an optical node device through which the optical path goes of the wavelength selection information.

Abstract: It is difficult to improve the wavelength-band utilization rate of an optical network as a whole while operating the optical network stably; and therefore, an optical network controller according to an exemplary aspect of the present invention includes optical wavelength region setting means for setting a wavelength region in an optical transmission line between a plurality of optical nodes composing an optical network using wavelength division multiplexing system dividing the wavelength region into consecutive regions of a first wavelength region and a second wavelength region; optical path setting means for setting a first optical path in the first wavelength region and a second optical path in the second wavelength region, the second optical path differing from the first optical path in a route; and control unit for instructing the plurality of optical nodes on a central wavelength and a usable band of signal light for the optical node to transmit based on a setting by the optical path setting means.

Abstract: It is difficult in an optical network to achieve fault recovery in case of multiple failures without decreasing the usage efficiency of the optical network; therefore, an optical communication system according to an exemplary aspect of the present invention includes an optical network management device including an optical path setting means for setting, to a physical route differing from each other, a backup path corresponding to each of a plurality of active paths on an identical physical route, and a failure-case optical path setting means for setting a failure-case backup path with a compressed band of the backup path, to a physical route without a failure in a case where failures arising on more than one physical route among the physical routes; and an optical node device including an optical transceiver means for transmitting and receiving optical signals using failure-case backup path information resulting from setting by the failure-case optical path setting means.

Abstract: If wavelength defragmentation is performed during the operation of an optical network, an instantaneous interruption of a network arises; consequently, data are lost; therefore, an optical network control method according to an exemplary aspect of the present invention includes monitoring a data volume of a client signal to be transmitted using a plurality of optical subcarriers; and performing synchronously, depending on a variation in the data volume, an optical subcarrier changing process of changing an active optical subcarrier, of the plurality of optical subcarriers, to be used for transmitting the client signal, and a remapping process of remapping the client signal onto an active optical subcarrier after having been changed.

Abstract: In a multi-layer network, a control load in the upper layer network increases, and the usage efficiency and the reliability of the entire network decrease; therefore, a multi-layer network system according to an exemplary aspect of the present invention includes a first network manager configured to set a logical path in a first network layer; and a second network manager configured to set a physical path corresponding to the logical path, in a second network layer, wherein the second network manager includes a network information storage configured to store physical network information including physical route information and transmission characteristic information on the second network layer, and the first network manager sets the logical path based on the physical network information.

Abstract: In an optical network system based on a wavelength division multiplexing system using a flexible frequency grid, with the diversification of optical modulation methods, the management burden on an optical network management device increases, and its control becomes complicated; therefore, an optical network system according to an exemplary aspect of the present invention includes an optical network management device configured to receive a traffic demand, design an optical path capable of accommodating the traffic demand, and create optical path design information of a design result; and an optical node device configured to be used for creating the optical path, wherein the optical node device calculates an allocable bandwidth from the optical path design information and optical node device information on a configuration of the optical node device, and the allocable bandwidth is an optical frequency bandwidth of a generable optical path that the optical node device is capable of generating, and the optical ne

Abstract: To provide signal generating apparatus that is capable of controlling the DC bias of the optical modulator applicable to various kinds of modulation format, a signal processing apparatus includes a digital processing unit for deserializing an input digital data into parallel data lanes, for comparing the value of the digital data of symbol rate F to at least one predetermined threshold value, for selecting an offset value based on the result of the comparison; and for adding the selected offset value to the digital data, a converting unit for converting the digital data added the offset value to analog signals in each lane; an optical modulating unit for modulating a lightwave according to the analog signals with predetermined modulation format at the symbol rate F, where the modulated signal contains a frequency component at F/N.

Abstract: It is difficult in an optical network to achieve fault recovery in case of multiple failures without decreasing the usage efficiency of the optical network; therefore, an optical communication system according to an exemplary aspect of the present invention includes an optical network management device including an optical path setting means for setting, to a physical route differing from each other, a backup path corresponding to each of a plurality of active paths on an identical physical route, and a failure-case optical path setting means for setting a failure-case backup path with a compressed band of the backup path, to a physical route without a failure in a case where failures arising on more than one physical route among the physical routes; and an optical node device including an optical transceiver means for transmitting and receiving optical signals using failure-case backup path information resulting from setting by the failure-case optical path setting means.

Abstract: In an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid, it is difficult to improve the usage efficiency of an optical frequency band owing to the occurrence of fragmentation of the optical frequency band; therefore, an optical network controller according to an exemplary aspect of the present invention includes an optical frequency region setting means for dividing an optical frequency band used in an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid, and setting a plurality of optical frequency regions; and an optical path setting means for setting optical paths having a common attribute in at least one of the plurality of optical frequency regions.

Abstract: It is difficult to build a highly efficient multicarrier optical transmission system because a multicarrier optical transmitter and receiver has limits on the degree of freedom when allocating optical transmission frames to optical subcarriers; therefore, a multicarrier optical transmitter according to an exemplary aspect of the present invention includes transmission-signal generating unit for accommodating a client signal in an optical transmission frame, dividing the optical transmission frame, and outputting divided frames to a plurality of lanes; optical transmission frame multiplex processing unit including a plurality of multiplexing units each of which time-division multiplexing the optical transmission frame inputted from a predetermined input lane included in the plurality of lanes and outputting a single multiplexed optical transmission frame; and optical transmission unit for modulating a plurality of optical subcarriers using a plurality of the multiplexed optical transmission frames respectively