DYNAMIC BAND ALLOCATION CIRCUIT, DYNAMIC BAND ALLOCATION METHOD, DYNAMIC BAND ALLOCATION PROGRAM, AND RECORDING MEDIUM

摘要

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 (targetj,k) which constitutes a target for allocated data size (allocatedj,k). Furthermore, taking the time constant of an exponential weighted moving average as τ, and taking α = (τ-1)/(τ+1), an ideal allocated data size (idealj,k) is calculated by idealj,k = targetj,k - (α/(1-α)) · excessj,k-1. Furthermore, an excess allocated data size (excessj,k) per one cycle is calculated by excessj,k = α ·excessj,k-1 + (1-α) · (allocatedj,k - targetj,k). If idealj,k0, the condition that bandwidth allocation is not granted is used for bandwidth allocation.