the present invention can be achieved by a base station in which a terminal is accommodated and the terminal is communicated with another terminal , and which includes : a data rate operation / management unit which operates and stores a time - averaged data rate rave of the terminal ; a threshold value operation / management unit which obtains a current communication data rate r of the terminal to operate and store r / rave ; and a delay management unit which controls to reduce delay on the basis of the r / rave .