Transmission method in network system using multiplex line, network

Abstract

In a network system, a plurality of terminals are serially connected using a multiplex line and the multiplex line includes at least one first channel for transmitting a cell in a first direction and at least one second channel for transmitting a cell in a second direction, which is opposite to the first direction. In a transmission method to be performed in the network system, a terminal out of the plural terminals, which has a request for writing data in a cell transmitted through the second channel, writes a write request in a cell transmitted through the first channel and having no write request written therein, and sends out this cell. Each of the plural terminals counts the number of a cell or cells having the write request written therein and transmitted through the first channel or channels. The terminal, which has sent out the cell having the write request written therein, writes data in a write-performable cell transmitted through the second channel and sends out this cell after allowing a write-performable cell or cells transmitted through the second channel or channels to pass. The number of the passing write-performable cell or cells is equal to the number of the cell or cells having the write request written therein, transmitted through the first channel or channels and counted before this terminal sends out the cell having the write request written therein.