Preliminary operation system in ATM network using flag for indicating preliminary operation mode

摘要

A preliminary operation system in an ATM network capable of preventing the erroneous cell transmissions due to the header transformation operation during the rewriting of the header transformation table, and recognizing cells of different cell types without using additional hardware components. The system includes a header transformation table for storing a header transformation information including a flag for indicating a preliminary operation mode either in a form of a state of the header transformation table or a type of cell for each cell; and a preliminary operation device for transforming a header of each cell into a format suitable for the ATM cell switch by utilizing the header transformation information stored in the header transformation table, according to the indication of the flag.