| 摘要 |
<p>PURPOSE:To prevent the characteristic of a cell class from being affected by the effect of a cell of a class with lower priority than that of the inputted cell by adding a class of abort and delay to a cell and providing an abort control section and a delay control section for the system. CONSTITUTION:A quality class CL(m, n) in response to an abort characteristic and a delay characteristic is added to a cell, and one buffer memory is divided into an area corresponding to the quality class CL(m, n) depending on the arrival quantity. When an inputted cell is written in an area of the quality class CL(m, n) corresponding the buffer memory, an abort control section 4 controls to abort a cell whose abort quality class is in excess of a independently preset threshold level corresponding to the total amount to be used of the buffer memory. A delay control section 5 applies priority control of the read sequence corresponding to the delay quality class at the read from the buffer memory. Thus, the abort characteristic and the delay characteristic are independently controlled and the characteristic is not affected by the cell with lower priority than that of its own cell.</p> |
