| 摘要 |
<p>In a P2MP system in which upstream bandwidth is shared by a plurality of ONUs, a dynamic bandwidth allocation circuit is provided which reduces the consumption of memory capacity, and avoids the divergence of parameters. A dynamic bandwidth allocation circuit provided in an optical line terminal (OLT) calculates, for each cycle and for each ONU, a target data size (target j,k ) which constitutes a target for allocated data size (allocated j,k ). Furthermore, taking the time constant of an exponential weighted moving average as Ä, and taking ± = (Ä-1)/(Ä+1), an ideal allocated data size (ideal j,k ) is calculated by ideal j,k = target j,k - (±/(1-±)) · excess j,k-1 . Furthermore, an excess allocated data size (excess j,k ) per one cycle is calculated by excess j,k = ± ·excess j,k-1 + (1-±) · (allocated j,k - target j,k ). If ideal j,k <0, the condition that bandwidth allocation is not granted is used for bandwidth allocation.</p> |
