METHOD FOR MEASURING SIGNAL TRANSMISSION DELAY TIME, CENTRAL STATION TO EXECUTE THIS METHOD, TERMINAL STATION AND NETWORK

摘要

PROBLEM TO BE SOLVED: To measure a signal transmission delay time between a terminal station among terminal stations and a central station without the use of a large distance identification window in the optical transmission network having plural terminal equipment stations connected to the central station through a tree connection structure. SOLUTION: A central station CS sends a start signal to a terminal station TSi and the terminal station TSi sends a distance identification signal to the central station CS in the lapse of a a prescribed time from the equipment of the start signal and the central station CS sends an inhibit signal to the terminal station TSi in the lapse of 2nd prescribed time after the transmission of the start signal so as to indicate it that no cell is to be sent for a period of an idle time window to the terminal station TSi. Then the central station CS estimates a signal transmission delay time from the content of the received distance identification signal for the period of the idle time window.