Method and device for acquiring information on links between mlds in wireless lan system

A first non-access point (non-AP) station (STA) in a wireless local area network (WLAN) system, the first non-AP STA comprising:

• a memory;
• a transceiver;
• and
• a processor being operatively connected to the memory and the transceiver,
• wherein the processor is configured to:
• transmit a multi-link probe request frame to a first AP;
• and
• receive a multi-link probe response frame from the first AP,
• wherein the first AP operating on a first link, a second AP operating on a second link and a third AP operating on a third link are affiliated with an AP multi-link device (MLD),
• wherein the first non-AP STA operating on the first link is affiliated with a non-AP MLD,
• wherein based on the multi-link probe request frame including per-STA profiles for the second AP and the third AP, only APs whose link ID is equal to a value in a Link ID field in the per-STA profiles for the second AP and the third AP in the multi-link probe request frame are the second AP and the third AP, and
• wherein the multi-link probe request frame allows the first non-AP STA to request information on all APs affiliated with the AP MLD, based on the multi-link probe request frame not including any per-STA profile.

A method in a wireless local area network (WLAN) system, the method comprising:

• receiving, by a first access point (AP), a multi-link probe request frame from a first non-AP station (STA);
• and
• transmitting, by the first AP, a multi-link probe response frame to the first non-AP STA,
• wherein the first AP operating on a first link, a second AP operating on a second link and a third AP operating on a third link are affiliated with an AP multi-link device (MLD),
• wherein the first non-AP STA operating on the first link is affiliated with a non-AP MLD,
• wherein based on the multi-link probe request frame including per-STA profiles for the second AP and the third AP, only APs whose link ID is equal to a value in a Link ID field in the per-STA profiles for the second AP and the third AP in the multi-link probe request frame are the second AP and the third AP, and
• wherein the multi-link probe request frame allows the first non-AP STA to request information on all APs affiliated with the AP MLD, based on the multi-link probe request frame not including any per-STA profile.