Abstract:
Identifier information (LLID) of an ONU and transfer instruction information indicating a transmission system as the output destination of a downstream frame are registered in a table (22) in correspondence with each of the destination IDs of the ONUs or user apparatuses connected to the ONUs. Upon receiving a downstream frame from a host apparatus, a frame transfer processing unit (20) acquires an LLID and transfer instruction information corresponding to the destination ID of the downstream frame from the table (22).
Abstract:
In a control frame processing unit (14), the number of control frames from a frame demultiplexing unit (13) is counted for each of LLIDs given to the control frames. If the number of frames during a predetermined count period is equal to or smaller than a preset threshold, some or all of the control frames are written in a storage device (30) as processing data. When the number of frames has exceeded the threshold, writing data of the control frames having the LLID in the storage device is stopped. Hence, even when the number of control frames from ONUs increases, software processing can be executed properly.
Abstract:
Identifier information (LLID) of an ONU and transfer instruction information indicating a transmission system as the output destination of a downstream frame are registered in a table (22) in correspondence with each of the destination IDs of the ONUs or user apparatuses connected to the ONUs. Upon receiving a downstream frame from a host apparatus, a frame transfer processing unit (20) acquires an LLID and transfer instruction information corresponding to the destination ID of the downstream frame from the table (22).
Abstract:
By using a combination of a plurality of completely unequally spaced channel allocations, the influence of four wave mixing is mitigated even while it is incompletely unequally spaced channel allocation, and it is possible both to decrease the occupied bandwidth and increase the number of channels. A plurality of completely unequally spacing channel allocations are combined, and the number of channels changes depending on the amount of scattering of an optical fiber and the frequency that there exists zero dispersion wavelengths on a transmission path. The completely unequally spaced channel allocations of N1-channels in a first wavelength region including the zero dispersion wavelength &lgr;0 or the mode zero dispersion wavelength &lgr;A are partitioned, and then in sequence the completely unequally spaced channel allocation of N2-, N3-, . . . , channels is partitioned, and the wavelength interval of N channels is set by combining all or a part thereof (where N1≧N224 . . . >Nj≧Nk−1≧Nk).