Line switching system and line switching unit of dynamic band variation unit

摘要

A line switching system of a dynamic band variation unit (10) having a function of connecting a dynamic data terminal device (30A) to an opposing data terminal device (30B) through a number of trunk lines such as a dedicated line (21) or ISDN lines (22-24), wherein the quantity of data to be sent out to a trunk line is varied after the quantity of data to be stored to the dynamic band variation unit is adjusted by varying the communication speed of the data transmitted from the dynamic data terminal unit, when varying the data communication quantity of the data terminal device by increasing or decreasing the number of trunk lines.