The present invention is directed to a wireless communication system. Specifically, the present invention is directed to a method of performing a procedure for link-setup and an apparatus therefore, wherein the method comprises: receiving a probe request frame including time information via a channel, wherein the time information indicates at least one of a minimum scan time for the channel and a maximum scan time for the channel; and performing a procedure for transmitting a probe response frame after receipt of the probe request frame, wherein if a beacon transmission time occurs within a time given based on the time information, transmission of the probe response frame is omitted.