ATM SWITCHING SYSTEM HAVING DUAL ATM SWITCH STRUCTURE

摘要

An ATM switching system includes two ATMswitches which are the same as each other. Each of theATM switches includes a switch buffer, and a cellcounter which indicates the number of cells in theswitch buffer. Each of the ATM switches also includesa difference calculator, which calculates thedifference between the number of cells in the twoswitch buffers when one of the ATM switches is changedfrom an out-of-service state to a slave mode. At thistime, the other ATM switch operates in a master mode.Each of the ATM switches further includes a dummy cellgenerator, which generates a number of dummy cellswhich corresponds to the difference calculated by thedifference calculator. The generated dummy cells arewritten into the switch buffer in the slave mode. Whenit is determined that when all of the dummy cells havebeen output from the switch buffer, the two ATMswitches are synchronized with each other.