PURPOSE: To make the packet quality control efficient and to improve the economy by selectively aborting a packet so as to apply congestion control while taking, delay time quality and abort rate quality into account.
CONSTITUTION: A packet is classified into plural sets of quality classes based on an allowable delay time and an allowable abort rate of a medium and a threshold level of a traffic is set to each quality class. A packet from a system bus 15 is processed by a CPU server 31 and transferred to a queue of a relevant class. In this case a length of the queue of its own line transmission queues 32, 33 is compared with a threshold level by the server 31 and when the length is within the threshold level, the packet is transferred to a line transmission queue. When the length is in excess of the threshold level, the system is discriminated to be in congestion, the packet of a class with a higher allowable abort rate is aborted and the resulting packet is transferred to the queue 32. On the other hand, a line server 34 scans the line transmission queues 32, 32 with a higher quality cyclicly and when the packets are resident, they are sequentially sent to a line 29. Thus, overload is controlled to suppress the deterioration in the quality to be within a prescribed value.
ARINO MASUYA
HORIUCHI YOSHITAKA
| JPH01221042A | 1989-09-04 | |||
| JPH02143636A | 1990-06-01 | |||
| JPH0250654A | 1990-02-20 | |||
| JPS63181583A | 1988-07-26 |