Early critical update indications for multi-link devices

1. A method for wireless communication performed by an access point (AP) multi-link device (MLD) including a first AP associated with a first communication link of the AP MLD and including one or more secondary APs associated with one or more respective secondary communication links of the AP MLD, the method comprising:

generating a frame by the first AP of the AP MLD, the frame including:

a first change sequence field carrying a first value of a most-recent critical update for the first AP of the AP MLD;

one or more secondary change sequence fields carrying second values of most-recent critical updates for respective secondary APs of the one or more secondary APs of the AP MLD; and

a critical update flag subfield carrying an indication of a change in value of at least one of the one or more secondary change sequence fields; and

transmitting the frame via the first communication link from the first AP of the AP MLD.

2. The method of claim 1 , wherein the most-recent critical update for the first AP corresponds to a change in one or more operation parameters of a basic service set (BSS) associated with the first AP of the AP MLD.

3. The method of claim 2 , wherein a second most-recent critical update for a respective secondary AP corresponds to a second change in one or more second operation parameters of the BSS associated with the respective secondary AP of the AP MLD.

4. The method of claim 2 , wherein the one or more operation parameters include at least one of a channel switch announcement (CSA), an extended CSA, a wide bandwidth CSA, enhanced distributed channel access (EDCA) parameters, multi-user (MU) EDCA parameters, a quiet time element, a direct sequence spread spectrum (DSSS) parameter set, a contention free (CF) parameter set, operating mode (OM) parameters, uplink (UL) orthogonal frequency division multiple access (OFDMA) random access (UORA) parameters, target wait time (TWT) parameters, BSS color change, fast initial link setup (FILS) parameters, spatial reuse (SR) parameters, a high-throughput (HT) operation, a very high-throughput (VHT) operation, a high efficiency (HE) operation, or an extremely high-throughput (EHT) operation.

5. The method of claim 1 , wherein the frame is one of a beacon frame, a probe response frame, an association response frame, a reassociation response frame, or a fast initial link setup (FILS) discovery frame.

6. The method of claim 1 , wherein the critical update flag subfield is carried in each beacon frame, or probe response frame, or both transmitted from the first AP during a time period.

7. The method of claim 6 , wherein the time period comprises a delivery traffic indication map (DTIM) period.

8. The method of claim 1 , further comprising:

transmitting all beacon frames within a delivery traffic indication map (DTIM) period with the indication of the change in value carried in the critical update flag subfield.

9. The method of claim 1 , wherein the critical update flag subfield is carried in a Capability Information field of a beacon frame or a probe response frame.

10. The method of claim 1 , further comprising:

incrementing a second value carried in a secondary change sequence field associated with a corresponding secondary AP responsive to a notification of a critical update for the corresponding secondary AP of the AP MLD; and

updating the critical update flag subfield in response to incrementing the second value carried in the secondary change sequence field associated with the corresponding secondary AP.

11. A method for wireless communication performed by a wireless station (STA) of a STA multi-link device (MLD), comprising:

associating with a first access point (AP) of an AP MLD, the AP MLD further including one or more secondary APs associated with one or more respective secondary communication links of the AP MLD; and

receiving a frame from the first AP via a first communication link of the AP MLD, the frame including:

a first change sequence field carrying a first value of a most-recent critical update for the first AP of the AP MLD;

one or more secondary change sequence fields carrying second values of most-recent critical updates for respective secondary APs of the one or more secondary APs of the AP MLD; and

a critical update flag subfield carrying an indication of a change in value of at least one of the one or more secondary change sequence fields.

12. The method of claim 11 , wherein the most-recent critical update for the first AP corresponds to a change in one or more operation parameters of a basic service set (BSS) associated with the first AP of the AP MLD.

13. The method of claim 12 , wherein a second most-recent critical update for a respective secondary AP corresponds to a second change in one or more second operation parameters of the BSS associated with the respective secondary AP of the AP MLD.

14. The method of claim 12 , wherein the one or more operation parameters include at least one of a channel switch announcement (CSA), an extended CSA, a wide bandwidth CSA, enhanced distributed channel access (EDCA) parameters, multi-user (MU) EDCA parameters, a quiet time element, a direct sequence spread spectrum (DSSS) parameter set, a contention free (CF) parameter set, operating mode (OM) parameters, uplink (UL) orthogonal frequency division multiple access (OFDMA) random access (UORA) parameters, target wait time (TWT) parameters, BSS color change, fast initial link setup (FILS) parameters, spatial reuse (SR) parameters, a high-throughput (HT) operation, a very high-throughput (VHT) operation, a high efficiency (HE) operation, or an extremely high-throughput (EHT) operation.

15. The method of claim 11 , wherein the frame is one of a beacon frame, a probe response frame, an association response frame, a reassociation response frame, or a fast initial link setup (FILS) discovery frame.

16. The method of claim 11 , wherein the critical update flag subfield is carried in a Capability Information field of a beacon frame or a probe response frame.

17. The method of claim 11 , wherein the frame is a beacon frame, and receiving the frame includes:

sequentially decoding a plurality of fields or elements of the beacon frame;

determining that the critical update flag subfield indicates the change in value of at least one of the first change sequence field or the one or more secondary change sequence fields; and

continuing the sequential decoding of the plurality of fields or elements of the beacon frame at least until the first change sequence field is decoded, irrespective of information carried in a traffic indication map (TIM) element of the beacon frame.

18. An access point (AP) multi-link device (MLD) including a first AP associated with a first communication link of the AP MLD and including one or more secondary APs associated with one or more respective secondary communication links of the AP MLD, the AP MLD comprising:

at least one modem;

at least one processor communicatively coupled with the at least one modem; and

at least one memory communicatively coupled with the at least one processor and storing processor-readable code that, when executed by the at least one processor in conjunction with the at least one modem, causes the AP MLD to perform operations comprising:

generating a frame by the first AP of the AP MLD, the frame including:

a first change sequence field carrying a first value of a most-recent critical update for the first AP of the AP MLD;

one or more secondary change sequence fields carrying second values of most-recent critical updates for respective secondary APs of the one or more secondary APs of the AP MLD; and

a critical update flag subfield carrying an indication of a change in value of at least one of the one or more secondary change sequence fields; and

transmitting the frame via the first communication link from the first AP of the AP MLD.

19. The AP MLD of claim 18 , wherein the most-recent critical update for the first AP corresponds to a change in one or more operation parameters of a basic service set (BSS) associated with the first AP of the AP MLD.

20. The AP MLD of claim 19 , wherein a second most-recent critical update for a respective secondary AP corresponds to a second change in one or more second operation parameters of the BSS associated with the respective secondary AP of the AP MLD.

21. The AP MLD of claim 18 , wherein the frame is one of a beacon frame, a probe response frame, an association response frame, a reassociation response frame, or a fast initial link setup (FILS) discovery frame.

22. The AP MLD of claim 18 , wherein the critical update flag subfield is carried in each beacon frame, or probe response frame, or both transmitted from the first AP during a time period.

23. The AP MLD of claim 18 , wherein execution of the processor-readable code by the at least one processor causes the AP MLD to perform operations further comprising:

transmitting all beacon frames within a delivery traffic indication map (DTIM) period with the indication of the change in value carried in the critical update flag subfield.

24. The AP MLD of claim 18 , wherein execution of the processor-readable code by the at least one processor causes the AP MLD to perform operations further comprising:

incrementing a second value carried in a secondary change sequence field associated with a corresponding secondary AP responsive to a notification of a critical update for the corresponding secondary AP of the AP MLD; and

updating the critical update flag subfield in response to incrementing the second value carried in the secondary change sequence field associated with the corresponding secondary AP.

25. The AP MLD of claim 18 , wherein the critical update flag subfield is carried in a Capability Information field of a beacon frame or a probe response frame.

26. A wireless station (STA) multi-link device (MLD), comprising:

at least one modem;

at least one processor communicatively coupled with the at least one modem; and

at least one memory communicatively coupled with the at least one processor and storing processor-readable code that, when executed by the at least one processor in conjunction with the at least one modem, causes the STA MLD to perform operations comprising:

associating with a first access point (AP) of an AP MLD, the AP MLD further including one or more secondary APs associated with one or more respective secondary communication links of the AP MLD, and

receiving a frame from the first AP via a first communication link of the AP MLD, the frame including:

a first change sequence field carrying a first value of a most-recent critical update for the first AP of the AP MLD;

one or more secondary change sequence fields carrying second values of most-recent critical updates for respective secondary APs of the one or more secondary APs of the AP MLD; and

a critical update flag subfield carrying an indication of a change in value of at least one of the one or more secondary change sequence fields.

27. The STA MLD of claim 26 , wherein the most-recent critical update for the first AP corresponds to a change in one or more operation parameters of a basic service set (BSS) associated with the first AP of the AP MLD.

28. The STA MLD of claim 27 , wherein a second most-recent critical update for a respective secondary AP corresponds to a second change in one or more second operation parameters of the BSS associated with the respective secondary AP of the AP MLD.

29. The STA MLD of claim 26 , wherein the critical update flag subfield is carried in a Capability Information field of a beacon frame or a probe response frame.

30. The STA MLD of claim 26 , wherein the frame is a beacon frame, and receiving the frame includes:

sequentially decoding a plurality of fields or elements of the beacon frame;

determining that the critical update flag subfield indicates the change in value of at least one of the first change sequence field or the one or more secondary change sequence fields; and

continuing the sequential decoding of the plurality of fields or elements of the beacon frame at least until the first change sequence field is decoded, irrespective of information carried in a traffic indication map (TIM) element of the beacon frame.