Method and apparatus for ascynchronous direct link setup in WLAN system

1. A method performed in a Wireless Local Access Network (WLAN) system, the method comprising:

establishing, by a first station, an access point (AP) link by associating with an AP;

receiving, by the first station, a direct link setup (DLS) request frame for requesting, through the AP, to set up a direct link from a second station, wherein the AP link is a communication link between the first station and the AP and the direct link is a communication link between the first station and the second station without passing through the AP;

determining, by the first station, at least one channel to be supported only in the direct link;

transmitting, by the first station, a DLS response frame for notifying the at least one channel to be used in the direct link as a response to the DLS request frame, through the AP to the second station, the DLS response frame including a status code and channel set information, the status code indicating a success or failure of the requested direct link setup, the channel set information indicating the at least one determined channel; and

communicating, by the first station, with the second station via the direct link by using the at least one determined channel,

wherein the first station and the second station are non-AP stations, and

wherein the channel set information is not processed by the AP during the receiving of the DLS request frame and the transmitting of the DLS response frame.

2. The method of claim 1 , further comprising:

receiving, by the first station, a channel reservation frame from the AP, the channel reservation frame including information about a reservation duration during which the at least one determined channel is used for the direct link.

3. The method of claim 1 , further comprising:

receiving, by the first station, a DLS control frame from the AP, the DLS control frame including information about a third station that participates in uplink or downlink transmission to the AP.

4. The method of claim 3 , wherein the DLS control frame further includes information about a transmission duration during which the uplink or downlink transmission is performed between the AP and the third station.

5. The method of claim 3 , wherein the DLS control frame is received when the communication for the direct link is terminated.

6. A device for a Wireless Local Access Network (WLAN) system, the device comprising:

a processor; and

a memory operatively coupled with the processor and storing instructions that when executed by the processor causes to the device to:

establish an access point (AP) link by associating with an AP;

receive a direct link setup (DLS) request frame for requesting, through the AP, to set up a direct link from a station, wherein the AP link is a communication link between the device and the AP and the direct link is a communication link between the device and the station without passing through the AP;

determine at least one channel to be supported only in the direct link;

transmit a DLS response frame for notifying the at least one channel to be used in the direct link as a response to the DLS request frame, through the AP to the station, the DLS response frame including a status code and channel set information, the status code indicating a success or failure of the requested direct link setup, the channel set information indicating the at least one determined channel; and

communicate with the station via the direct link by using the at least one determined channel,

wherein the device and the station are non-AP stations, and

wherein the channel set information is not processed by the AP during the receiving of the DLS request frame and the transmitting of the DLS response frame.