According to an aspect of present invention provides method of controlling a packet transmission interval, method comprising, comparing a preset delay ratio with number of packets transmitted, transmitting packets until number of packets transmitted becomes equal to or greater than delay ratio, calculating a delay request time when number of packets transmitted becomes equal to or greater than delay ratio, generating a signal for suspending packet transmission during calculated delay request time, suspending packet transmission according to generated signal and calculating a gap time based on a difference between a time when suspension of packet transmission was terminated and packet transmission was started and updating the delay ratio using the calculated gap time and initializing the number of packets transmitted.