Patent ID: 7881271

Claim:
A wireless LAN system established by connecting a plurality of communication stations via a network, comprising: a first communication station, when the first communication station transmits packets to a second communication station, can select a first method in which the second communication station returns first transmission-confirmation information to the first communication station for each packet that the second communication station receives, and a second method in which the second communication station returns, in response to the request of the first communication station, second transmission-confirmation information to the first communication station for a plurality of received packets, the first communication station can select either one of the first method and the second method, based on a number k of packets to be acknowledged by the second transmission-confirmation information, and the second method is selected when k>(tBAR+tBA+tNA+3SIFS)/(tNA+SIFS), where tNA represents a transmission period of the first transmission-confirmation information, SIFS represents a short frame interval, tBAR represents a transmission period of the request, and tBA represents a transmission period of the second transmission-confirmation information.