Device and method for multi-link communications

1. A device comprising:

a processor configured to:

identify that a critical update event has occurred on a first link of an access point (AP) multi-link device (MLD); and

transmit a management frame on a second link,

wherein the management frame includes a Change Sequence field and a multi-link (ML) element that indicates the critical update event;

wherein the processor is configured to set the Change Sequence field to a Change Sequence value before the critical update event; and

wherein the processor is configured to keep the Change Sequence field set to the Change Sequence value after the critical update event.

2. The device of claim 1 ,

wherein the processor is configured to a not increment the Change Sequence value included in the Change Sequence field during transmission of the management frame when the ML element includes at least one of:

a Channel Switch Announcement (CSA) element;

an extended CSA (eCSA) element;

a Quiet element; and

a Quiet Channel element.

3. The device of claim 2 ,

wherein the processor is configured to increment a Check Beacon value included in a Check Beacon field of a Traffic Indication Map (TIM) frame transmitted by the AP MLD subsequent to the transmission of the management frame.

4. The device of claim 1 ,

wherein the processor is configured to increment a Change Sequence value included in the Change Sequence field during transmission of the management frame when the ML element includes at least one of:

an Enhanced Distribution Channel Access (EDCA) Parameter Set element;

a multi-user (MU) EDCA Parameter Set element; and

an Operation element.

5. The device of claim 1 ,

wherein the critical update event is for a first AP associated with the AP MLD on the first link, and

wherein a second AP associated the AP MLD is configured to not increment the Change Sequence value included in the Change Sequence field of the management frame transmitted on the second link.

6. The device of claim 1 ,

wherein the critical update event is for a first AP associated with the AP MLD on the first link, and

wherein the Change Sequence value for the first AP remains unchanged.

7. The device of claim 1 ,

wherein a first AP associated with the AP MLD includes scheduling information for a restricted Service Period (SP), and wherein a second AP associated the AP MLD transmits the scheduling information for the restricted SP via the management frame on the second link.

8. The device of claim 7 ,

wherein the scheduling information for the restricted SP is indicated by a TWT element included in the ML element of the management frame.

9. The device of claim 7 ,

wherein the scheduling information is for non-AP stations (STAs) of a non-AP MLD associated with the AP MLD, and

wherein a non-AP STA that is not scheduled by the scheduling information ends a Transmission Opportunity (TXOP) before the restricted SP.

10. The device of claim 7 ,

wherein the scheduling information is for non-AP STAs of a non-AP MLD associated with the AP MLD, and

wherein a non-AP STA that is scheduled by the scheduling information ends a TXOP before the restricted SP.

11. The device of claim 1 ,

wherein the ML element includes a Quiet element that indicates a quiet interval during which a non-AP STA is not allowed to access a medium.

12. The device of claim 11 , wherein the non-AP STA ignores the quiet interval when the quiet interval overlaps with a restricted Service Period (SP), and wherein the non-AP STA is allowed to access the medium during the restricted SP.

13. The device of claim 1 ,

wherein a first AP associated with the AP MLD on the first link identifies the update event, and

wherein a second AP associated the AP MLD transmits the management frame on the second link.

14. The device of claim 1 ,

wherein the update event is included in a per-STA profile sub-element of the ML element, and

wherein the per-STA profile sub-element corresponds to an AP of the AP MLD.

15. The device of claim 1 ,

wherein the management frame is at least one of a beacon frame and a probe response frame.

16. The device of claim 1 ,

wherein the processor is configured to operate according to an Institute of Electrical and Electronics Engineers (IEEE) 802.11be communication protocol.

17. The device of claim 1 ,

wherein the device is a wireless local area network (WLAN) device.

18. A method for multi-link communications, the method comprising:

identifying, by an access point (AP) multi-link device (MLD), that a critical update event has occurred on a first link;

transmitting, by the AP MLD, a management frame on a second link,

wherein the management frame includes a Change Sequence field and a multi-link (ML) element that indicates the critical update event;

wherein the Change Sequence field includes a Change Sequence value; and

after the critical update event, keeping the Change Sequence value same as from before the critical update event.

19. The method of claim 18 , wherein the method includes:

receiving, by a non-AP MLD from the AP MLD, the management frame on the second link; and

operating the non-AP MLD according to the management frame received on the second link.

20. The method of claim 19 , wherein operating the non-AP MLD includes:

identifying whether a non-AP station (STA) associated with the non-AP MLD needs to monitor other management frames transmitted by the AP MLD.

21. A device comprising: a processor configured to: identify that an update event has occurred on a first link of an access point (AP) multi-link device (MLD); and transmit a management frame on a second link, wherein the management frame includes a Change Sequence field and a multi-link (ML) element that indicates the update event; wherein the ML element includes a Quiet element that indicates a quiet interval during which a non-AP STA is not allowed to access a medium; wherein the non-AP STA ignores the quiet interval when the quiet interval overlaps with a restricted Service Period (SP), and wherein the non-AP STA is allowed to access the medium during the restricted SP.