DATA TRANSMISSION SYSTEM

摘要

A data transmission system including first and second stations. In the first station, after data is separated into multiple sets of data, sequential transmission numbers are added to them to generate frames, which are sent. The second station receives these frames. When the second station cannot receive some frames normally, the number of continuous erroneous frames is compared with a threshold. If the number is equal to or more than the threshold, the second station requests the first station to resend all the data sets having the specified and later transmission numbers by the GBN method. If the number is smaller than the threshold, the second station requests the first to resend only the data having the specified transmission number by the SR method. The threshold is so determined as to be optimal depending on the status of the data transmission taking the resource and performance into consideration.