IP Library › Granted Patent US 12,538,274
Granted Patent B2
US 12,538,274 · App. 18/059,500 · Granted Jan 27, 2026

Excess slot-time re-farming

Inventors: Malcolm Smith (Richardson, TX); Brian Hart (Sunnyvale, CA)
H04W72/0446
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Quick Facts
Patent No.
US 12,538,274
App. No.
18/059,500
Granted
Jan 27, 2026
Kind
B2
Abstract

Excess slot-time re-farming may be provided. A slot allocation may be received by a first Access Point (AP). Next, excess time in the slot allocation may be determined. Then wireless exchanges may be used to allocate the excess time in the slot allocation to a second AP.

Claims (45)

1 . A method comprising:

receiving, by a first Access Point (AP), a slot allocation;

determining excess time in the slot allocation; and

using wireless exchanges to allocate the excess time in the slot allocation to a second AP, wherein using the wireless exchanges to allocate the excess time in the slot allocation to the second AP comprises:

providing a slotend frame at a pre-determined offset in the slot allocation, wherein the slotend frame indicates an end and causes other APs to contend for the excess time in the slot allocation,

transmitting by each of the other APs the slotend frame at the pre-defined offset, wherein the other APs only stop transmitting when they have heard slotend frames from all of the other APs, and

contending, by the other APs, for the excess time after stopping the transmitting.

2 . The method of claim 1 , wherein the second AP comprises one of the other APs.

3 . The method of claim 1 , wherein using wireless exchanges to allocate the excess time in the slot allocation to a second AP comprises using Network Allocation Vector (NAV) to indicate an end.

4 . The method of claim 3 , wherein using the NAV to indicate the end causes other APs to contend for the excess time in the slot allocation wherein the second AP comprises one of the other APs.

5 . The method of claim 4 , wherein using wireless exchanges to allocate the excess time in the slot allocation comprises using wireless exchanges to allocate the excess time in the slot allocation based on priority of buffered traffic.

6 . The method of claim 4 , wherein using wireless exchanges to allocate the excess time in the slot allocation comprises using wireless exchanges to allocate the excess time in the slot allocation based on priority of buffered traffic and in one of in turn and in parallel.

7 . A system comprising:

a memory storage; and

a processing unit coupled to the memory storage, wherein the processing unit is configured to:

receive a slot allocation;

determine excess time in the slot allocation; and

use wireless exchanges to allocate the excess time in the slot allocation to a second AP, wherein the processing unit being configured to use the wireless exchanges to allocate the excess time in the slot allocation to the second AP comprises the processing unit being configured to:

provide a slotend frame at a pre-determined offset in the slot allocation that indicates an end and causes other APs to contend for the excess time in the slot allocation,

transmit by each of the other APs the slotend frame at the pre-defined offset, wherein the other APs only stop transmitting when they have heard slotend frames from all of the other APs, and

contend, by the other APs, for the excess time after stopping the transmitting.

8 . The system of claim 7 , wherein the second AP comprises one of the other APs.

9 . The system of claim 7 , wherein using wireless exchanges to allocate the excess time in the slot allocation to a second AP comprises using Network Allocation Vector (NAV) to indicate an end.

10 . The system of claim 9 , wherein using the NAV to indicate the end causes other APs to contend for the excess time in the slot allocation wherein the second AP comprises one of the other APs.

11 . The system of claim 10 , wherein using wireless exchanges to allocate the excess time in the slot allocation comprises using wireless exchanges to allocate the excess time in the slot allocation based on priority of buffered traffic.

12 . The system of claim 10 , wherein using wireless exchanges to allocate the excess time in the slot allocation comprises using wireless exchanges to allocate the excess time in the slot allocation based on priority of buffered traffic and in one of in turn and in parallel.

13 . A non-transitory computer-readable medium that stores a set of instructions which when executed perform a method executed by the set of instructions comprising:

receiving, by a first Access Point (AP), a slot allocation;

determining excess time in the slot allocation; and

using wireless exchanges to allocate the excess time in the slot allocation to a second AP, wherein using the wireless exchanges to allocate the excess time in the slot allocation to the second AP comprises:

providing a slotend frame at a pre-determined offset in the slot allocation that indicates an end and causes other APs to contend for the excess time in the slot allocation,

transmitting by each of the other APs the slotend frame at the pre-defined offset, wherein the other APs only stop transmitting when they have heard slotend frames from all of the other APs, and

contending, by the other APs, for the excess time after stopping the transmitting.

14 . The non-transitory computer-readable medium of claim 13 , wherein the second AP comprises one of the other APs.

15 . The non-transitory computer-readable medium of claim 13 , wherein using wireless exchanges to allocate the excess time in the slot allocation to a second AP comprises using Network Allocation Vector (NAV) to indicate an end.

16 . The non-transitory computer-readable medium of claim 15 , wherein using the NAV to indicate the end causes other APs to contend for the excess time in the slot allocation wherein the second AP comprises one of the other APs.

17 . The non-transitory computer-readable medium of claim 16 , wherein using wireless exchanges to allocate the excess time in the slot allocation comprises using wireless exchanges to allocate the excess time in the slot allocation based on priority of buffered traffic.

18 . The method of claim 1 , wherein using the wireless exchanges to allocate the excess time in the slot allocation to the second AP comprises using the wireless exchanges to allocate the excess time in the slot allocation to the second AP after prior inter-AP wired coordination with the other APs via Carrier-Sense Multiple Access with Collision Avoidance (CSMA/CA).

19 . The method of claim 1 , wherein the inter-AP wired coordination with the other APs via CSMA/CA comprises one of the following:

determining that the excess time is greater than a predetermined value; and

determining that a wired connection to the other APs is rearchitected to provide a low latency wired path from a Media Access Control (MAC) to a peer MAC.

20 . The method of claim 1 , wherein using the wireless exchanges to allocate the excess time in the slot allocation to the second AP comprises:

polling neighboring APs to determining how much traffic they have per Access Class (AC)/Traffic Identifier (TID) and for how long a head of line traffic has been buffered; and

in response to receiving no response to the polling, transmitting a predetermined fraction of Transmit Opportunity (TXOP) within its Basic Service Set (BSS); and

re-polling the neighboring APs.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 29, 2022
From: SMITH, MALCOLM; HART, BRIAN
To: CISCO TECHNOLOGY, INC.
Reel/Frame 061902/0433 →
Continuity (1)
Related Publication 20240179687A1 · May 30, 2024
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