Apparatus and method of monitoring a queue state in an asynchronous transfer mode switch

摘要

Disclosed is an apparatus and method of monitoring the queue state of a switch in the subscriber board of an asynchronous transfer mode switching system. A difference value between the present time value and a previous input time value stored in a memory per connection is inputted to a forward resource management (FRM) cell when a resource management (RM) cell is inputted from a source, and a switch load measurement value written in the FRM cell is obtained by calculating the difference value between the present time value and a previous output time value stored in the memory per connection when the FRM cell transmitted from the source passes through the switch. The obtained switch load measurement value is inputted to a backward resource management (BRM) cell transmitted from a destination to be transmitted to the switch. The queue state of the switch is determined by identifying the switch load measurement value which is applied to the BRM cell that is transmitted from the destination via the switch, then an explicit cell rate (ER) value is calculated according to the queue state of the switch and the ER value is applied to the BRM cell to be transmitted to the source.