METHOD FOR CHECKING DATA CELL TRANSFER IN ASYNCHRONOUS EXCHANGE SYSTEM, BASIC EXCHANGE DEVICE USED THERFOR AND NETWORK

摘要

PROBLEM TO BE SOLVED: To provide a method for checking the data cell transfer of an asynchronous exchange system. SOLUTION: Cells are periodically marked and counted before entering the system. A periodical time frame consisting of N pieces of interleaving check cycles is given. Each check cycle C1 comprises a first step IC1 for marking and counting the cells before exchange after it receives the cells and a second count step OC1 for counting after exchange. An identifying mark linked with the position of the check cycle in a time frame is given to every cell that is received in the first step of each check cycle. When the marked cells are exchanged in the second step of the check cycle, they are immediately counted. The second step is started after a prescribed delay d1 with respect to the first step and continued for a prescribed time t2. Correspondence between two counts obtained during one check cycle is decided and a fault signal is immediately issued when the decided correspondence is obtained.