Apparatus and system for learning Wi-Fi access point behavior to reduce power consumption

Abstract

The invention discloses an apparatus and system for learning Wi-Fi access point behavior to reduce power consumption. A method and Wi-Fi apparatus for learning behavior of associated access points and modifying their action accordingly are disclosed. The low power Wi-Fi device may begin in a default state and observe the behavior of the access point. Based on this observed behavior, the low power Wi-Fi device may continue to operate in a default state, or may modify its action. Some of the behaviors of the monitored access point include its response to PS-Pool packets, its "keep active" behavior, and its aggregated use. In each case, the low power Wi-Fi device can modify its action if the access point operates in a different manner than the expected manner. As a result of the modification, the low power Wi-Fi device may reduce its power consumption.

Description

[0001] This application claims priority to U.S. patent application serial number 18 / 588,482, filed on February 27, 2024, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] This disclosure describes systems and various methods that learn the behavior of access points in a Wi-Fi network and adapt the operation of wireless devices based on that learning. Background Art

[0003] The Wi-Fi protocol was originally designed to include devices that could draw unlimited power. Consequently, early revisions of the specification did not include any provisions for supporting very low-power devices that need to enter low-power modes to conserve battery life. For example, some devices, such as sensor devices, ideally should have a battery life of more than a year.

[0004] The Wi-Fi protocol has been updated to include several power-saving operating modes. For example, one such update is the inclusion of PS-Poll. In this mode, a low-power Wi-Fi device notifies the access point that it is entering sleep mode. The access point will then buffer all outbound messages for that low-power Wi-Fi device. If it has any outbound packets for that device, it indicates this in its beacon message using the Traffic Indication Map (TIM) bit for that device. After waking up, the low-power Wi-Fi device checks the TIM bit in the beacon and, if there are stored messages, it transmits a PS-Poll packet to the access point, requesting the stored packets.

[0005] According to the specification, the access point then transmits the buffered packets to the low-power Wi-Fi device. If there are multiple buffered packets, the access point sets the "more data" bit in all but the last packet, indicating to the low-power Wi-Fi device that there are more buffered packets to retrieve.

[0006] While this feature allows devices in a Wi-Fi network to have a low power mode, there are complexities associated with this feature that need to be addressed. For example, some access points utilize the TIM bit but cannot properly respond to PS-Poll packets.

[0007] Another issue is the use of "keep alive" or "heartbeat" messages by access points. Some access points transmit "keep alive" messages when low-power Wi-Fi devices are in sleep mode. Other access points exhibit other behaviors to maintain TCP connections.

[0008] Other anomalies in access point behavior have also been observed. Some of these behaviors may result in increased power consumption by low-power Wi-Fi devices.

[0009] Therefore, it would be beneficial if there were a system and method by which a low-power Wi-Fi device could learn the behavior of an access point and modify its own actions accordingly. These modifications could be used to reduce the power consumption of the low-power Wi-Fi device. Summary of the Invention

[0010] Methods and Wi-Fi devices are disclosed for learning the behavior of associated access points and modifying their actions accordingly. A low-power Wi-Fi device can begin in a learning state and observe the behavior of the access point. Based on this observed behavior, the low-power Wi-Fi device can continue to operate in a default state or modify its behavior. Some of the monitored access point behaviors include its response to PS-Poll packets, its "keep alive" behavior, and its use of aggregation. In each case, if the access point operates differently than expected, the low-power Wi-Fi device can modify its behavior. As a result of the modifications, the low-power Wi-Fi device can reduce its power consumption.

[0011] According to one embodiment, a method of operating a low-power Wi-Fi device is disclosed. The method includes observing the behavior of an access point while the low-power Wi-Fi device is in a default operating state; and if the behavior differs from expected behavior, modifying the operation of the low-power Wi-Fi device to reduce transmissions or power consumption. In some embodiments, the low-power Wi-Fi device observes the access point's response to a PS-Poll message. In certain embodiments, if the access point does not respond to the PS-Poll message, the low-power Wi-Fi device modifies operation by transmitting packets with a power management (PM) bit set to 0 or 1 to indicate when the low-power Wi-Fi device is in active mode and power save mode, respectively. In certain embodiments, the packets transmitted with the PM bit set to 0 or 1 are NULL packets, Quality of Service (QoS) packets, data packets, or QoS data packets. In some embodiments, when the low-power Wi-Fi device is in power save or sleep mode, the low-power Wi-Fi device observes the number of "keep alive" messages transmitted by the access point. In certain embodiments, if the number of "keep alive" messages is less than a predetermined threshold, the low-power Wi-Fi device utilizes PS-Poll messages. In certain embodiments, if the number of "keep alive" messages is greater than a predetermined threshold, the low-power Wi-Fi device modifies operation by transmitting packets with the power management (PM) bit set to 0 to indicate that the low-power Wi-Fi device is in active mode. In some embodiments, the low-power Wi-Fi device observes the number and type of TIDs (traffic identifiers) for which the access point requests an aggregated context. In certain embodiments, if the low-power Wi-Fi device has continuous or bursty data associated with the TID, it establishes an aggregated context. In certain embodiments, if the low-power Wi-Fi device has occasional data associated with the TID, the low-power Wi-Fi device modifies operation by rejecting the request and transmitting packets with the power management (PM) bit set to 0 to indicate that the low-power Wi-Fi device is in active mode. In some embodiments, the method includes exiting the modified mode of operation after a predetermined amount of time or a predetermined number of packets and repeating the observation. In some embodiments, the method includes exiting the modified mode of operation and repeating the observation if the connection between the low-power Wi-Fi device and the access point is terminated.

[0012] According to another embodiment, a low-power Wi-Fi device is disclosed. The device includes a Wi-Fi network interface; a processing unit; and a memory device in communication with the processing unit, the memory device containing instructions that, when executed by the processing unit, enable the low-power Wi-Fi device to: observe the behavior of an access point when the low-power Wi-Fi device is in a default operating state; and if the behavior differs from expected behavior, modify the operation of the low-power Wi-Fi device to reduce transmissions or power consumption. In some embodiments, the low-power Wi-Fi device observes the access point's response to a PS-Poll message. In certain embodiments, the memory device further includes instructions that enable the low-power Wi-Fi device to: if the access point does not respond to the PS-Poll message, modify the operation by transmitting a packet with a power management (PM) bit set to 0 or 1 to indicate when the low-power Wi-Fi device is in active mode and power save mode, respectively. In some embodiments, when the low-power Wi-Fi device is in power save or sleep mode, the low-power Wi-Fi device observes the number of "keep alive" messages transmitted by the access point. In certain embodiments, the memory device further includes instructions that enable the low-power Wi-Fi device to: transmit a PS-Poll message if the number of "keep alive" messages is less than a predetermined threshold; and transmit a packet with the power management (PM) bit set to 0 to indicate that the low-power Wi-Fi device is in active mode if the number of "keep alive" messages is equal to or greater than the predetermined threshold. In some embodiments, the low-power Wi-Fi device observes the number and type of TIDs (traffic identifiers) for which an aggregated context is requested by the access point. In certain embodiments, the memory device further includes instructions that enable the low-power Wi-Fi device to: establish an aggregated context if the low-power Wi-Fi device has continuous or bursty data associated with the TID; and reject the request and transmit a packet with the power management (PM) bit set to 0 to indicate that the low-power Wi-Fi device is in active mode if the low-power Wi-Fi device has occasional data associated with the TID. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] For a better understanding of the present disclosure, reference is made to the accompanying drawings, in which like elements are represented by like numerals, and in which: Figure 1 shows a block diagram of a Wi-Fi network device; Figure 2 A system including a Wi-Fi network is shown; Figure 3 shows a general flow chart highlighting the operation of a low power Wi-Fi device; Figure 4A first example of operation based on modification of a response to a PS-Poll packet is shown; Figure 5A-5B A second example of operation is shown that is modified based on the number of "keep-alive" packets sent; and Figure 6 A third example of operation based on modification of an aggregated context requested by an access point is shown. DETAILED DESCRIPTION

[0014] The present disclosure proposes systems and methods for learning the behavior of access points in a Wi-Fi network and adapting the operation of a device based on that learning.

[0015] Figure 1 A block diagram of a representative Wi-Fi device 10 that may be used to implement the disclosed method of minimizing power consumption in a Wi-Fi network is shown.

[0016] Wi-Fi device 10 has a processing unit 20 and an associated memory device 25. Processing unit 20 can be any suitable component, such as a microprocessor, an embedded processor, a dedicated circuit, a programmable circuit, a microcontroller, or another similar device. Memory device 25 contains instructions 26 that, when executed by processing unit 20, enable Wi-Fi device 10 to perform the functions described herein. Memory device 25 can be a non-volatile memory, such as a flash ROM, an electrically erasable ROM, or other suitable device. In other embodiments, memory device 25 can be a volatile memory, such as RAM or DRAM.

[0017] Although a memory device 25 is disclosed, any computer readable medium may be used to store the instructions. For example, a read-only memory (ROM), a random access memory (RAM), a magnetic storage device such as a hard drive, or an optical storage device such as a CD or DVD may be used. In addition, the instructions may be downloaded to the memory device 25, such as, for example, over a network connection (not shown), via a CD ROM, or through another mechanism. The instructions may be written in any programming language, which is not a limitation of the present disclosure. Therefore, in some embodiments, there may be multiple computer readable non-transitory media containing the instructions described herein. Figure 1 As shown in FIG, a first computer-readable non-transitory medium can be in communication with the processing unit 20. A second computer-readable non-transitory medium can be a CDROM or a different memory device located remotely from the Wi-Fi device 10. The instructions contained on the second computer-readable non-transitory medium can be downloaded to the memory device 25 to allow execution of the instructions by the Wi-Fi device 10.

[0018] The Wi-Fi device 10 also includes a Wi-Fi network interface 30 that connects to the Wi-Fi network 100 using an antenna 35 .

[0019] The Wi-Fi device 10 may include a data storage device 40 in which data received and transmitted by the Wi-Fi network interface 30 is stored. The data storage device 40 is conventionally a volatile memory. The processing unit 20 has the ability to read and write to the data storage device 40 in order to communicate with other devices in the Wi-Fi network 100.

[0020] In addition, the Wi-Fi device 10 may include a timer 50. The timer 50 may be used to measure a time duration. In addition, the timer 50 may be used to wake up the processing unit 20 from its low power or sleep mode.

[0021] Although not shown, the Wi-Fi device 10 also has a power supply, which may be a battery or a connection to a permanent power source, such as a wall outlet.

[0022] Although the processing unit 20, the memory device 25, the Wi-Fi network interface 30, the data storage device 40 and the timer 50 are Figure 1 are shown as separate components, but it is understood that some or all of these components may be integrated into a single electronic assembly. Figure 1 It is used to illustrate the functionality of the Wi-Fi device 10 rather than its physical configuration.

[0023] In the awake state, all of the above components can be powered. In a low power mode, also known as power saving or sleep mode, one or more of these components can be in sleep mode or powered off.

[0024] Figure 2 A system including a Wi-Fi network 100 is shown. The Wi-Fi network 100 includes a low-power Wi-Fi device 110 and an access point 120, both of which may have Figure 1 . In other words, low-power Wi-Fi device 110 and access point 120 are both Wi-Fi network devices. Low-power Wi-Fi device 110 may have a battery as a power source and may include a lower power processing unit and less memory capacity than access point 120.

[0025] Access point 120 can also communicate with a local area network (LAN). The LAN can be an Ethernet network, although other types of networks can also be used. Disposed on the LAN can also be one or more LAN devices 130. These LAN devices 130 can include printers, personal computers, servers, and other devices. In addition, a gateway 140 can communicate with the LAN and allow access to the Internet 150.

[0026] Figure 3 A general flow chart illustrating the operation of a low-power Wi-Fi device is shown. First, the low-power Wi-Fi device 110 is initialized to a learning state 300. While in this learning state 300, the low-power Wi-Fi device 110 observes the behavior of the access point 120. These observations may include detecting the number and / or type of packets sent by the access point 120, or by detecting the access point 120's responses to packets sent by the low-power Wi-Fi device 110. While in this learning state 300, the low-power Wi-Fi device operates using its default operating mode. After observing the behavior of the access point 120, the low-power Wi-Fi device 110 determines whether the access point 120's behavior is as expected or different from expected. If the access point's behavior is as expected, no changes are made to the operation of the low-power Wi-Fi device 110, and it enters the default operating state 310. However, if the observed behavior is different from the expected behavior, the low-power Wi-Fi device 110 modifies its operation and enters the modified operating state 320. This modification of its operation can enable the low-power Wi-Fi device 110 to reduce its power consumption. Once the low-power Wi-Fi device 110 completes its learning, it remains in the selected state (default operating state 310 or modified operating state 320) until the connection with the access point 120 is terminated. In addition, in some embodiments, when operating in the modified operating state 320, the low-power Wi-Fi device 110 can periodically return to the learning state 300 to determine whether the operation of the access point 120 has changed.

[0027] This approach can be used to observe many different possible behaviors.

[0028] Figure 44 shows a first behavior that can be monitored. One aspect in which the behavior of the access points 120 differs is their response to PS-Poll packets. As shown in block 400, when the low-power Wi-Fi device 110 enters power save mode, it transmits a packet with the PM (power management) bit set to 1. This can be a NULL packet, a QOS (quality of service) packet, a data packet, or a QOS data packet. In response, the access point 120 will now buffer any packets destined for the low-power Wi-Fi device 110, as shown in block 410. Once there are any buffered packets for the low-power Wi-Fi device in the access point 120, it will assert the TIM bit in its beacon for the low-power Wi-Fi device 110, as shown in block 420. As shown in block 430, when the low-power Wi-Fi device 110 exits power save or sleep mode, it checks the TIM bit in the beacon. If the TIM bit corresponding to the Wi-Fi device is set to 1, low-power Wi-Fi device 110 attempts to retrieve a packet (or packets) from access point 120 by transmitting a PS-Poll packet to access point 120, as shown in block 440. Low-power Wi-Fi device 110 then waits for a response, as shown in decision block 445. In response, access point 120 may transmit an acknowledgment to low-power Wi-Fi device 110, followed by the first of the buffered packets. In this case, the low-power Wi-Fi device receives the acknowledgment and the packet, as shown in block 450. This is known as expected behavior. If that packet has the "More Data" bit set, low-power Wi-Fi device 110 will transmit another PS-Poll packet, as shown in decision blocks 455 and 460. This behavior repeats until the "More Data" bit is no longer set, at which point low-power Wi-Fi device 110 returns to power saving or sleep mode, as shown in block 465. However, some access points may not respond to PS-Poll data packets. This is known as unexpected behavior. In response, the low power Wi-Fi device 110 may retransmit the PS-Poll packet one or more additional times in case the earlier packet was not received by the access point 120. This is shown in block 470. The low power Wi-Fi device 110 then checks for a response, as shown in decision block 475. If the access point 120 responds to one of these retransmissions, the low power Wi-Fi device 110 assumes this is expected behavior and receives the packet as shown in block 450 and continues using the default operating mode as described above. However, if the access point 120 does not respond, the low power Wi-Fi device modifies its operation, as shown in block 480. This modified operation may include the following sequence. First, the low power Wi-Fi device 110 transmits a packet with the power management (PM) bit set to 0, indicating that it is in active mode, as shown in block 481.Note that this packet can be a NULL packet, a QOS NULL packet, a data packet, or a QOS data packet. It then receives all of the buffered packets, as shown in block 482. Once it concludes that all buffered packets have been received, the low-power Wi-Fi device 110 transmits the packet with PM=1 and returns to power saving or sleep mode, as shown in block 483.

[0029] Note that in one embodiment, once the low power Wi-Fi device 110 modifies its operation, that modification may remain in effect as long as the low power Wi-Fi device 110 is connected to the access point 120. Figure 4 If the low power Wi-Fi device 110 has modified its behavior, the next time it exits power save or sleep mode, it executes block 430, and if the TIM bit is set, the low power Wi-Fi device 110 proceeds directly to block 481. In this way, the low power Wi-Fi device 110 does not consume power transmitting and then retransmitting the PS-Poll packet to the access point 120. Thus, blocks 480-483 constitute the modified operating state 320, as described with reference to FIG. Figure 3 As stated.

[0030] In another embodiment, as referenced Figure 3 As explained, the low power Wi-Fi device 110 may modify its behavior only for a predetermined amount of time. In this embodiment, the low power Wi-Fi device tracks the duration of time it has been in the modified operating state 320. Once that duration reaches a predetermined threshold, the low power Wi-Fi device 110 returns to the learning state 300 by attempting to determine whether the access point 120 is capable of processing the PS-Poll message via blocks 430 and 440.

[0031] When using the modified operation, the low power Wi-Fi device 110 may track the number of buffered packets it retrieves from the access point 120, rather than usage time. The low power Wi-Fi device 110 may re-enter the learning state 300 after retrieving a predetermined number of buffered packets.

[0032] Figures 5A-5B Another example of modified operation based on the behavior of access point 120 is shown. This example relates to the behavior of access point 120 regarding "keep-alive" messages. Access point 120 may periodically send "keep-alive" messages. These may be NULL packets or QOS NULL packets. Access point 120 may transmit a burst of "keep-alive" messages, where the burst may include 1, 2, or 3 packets. Based on this value, low-power Wi-Fi device 110 determines how to operate when waking from sleep mode. Figure 5AThe learning or characterization process is shown. First, as noted in block 500, the low-power Wi-Fi device 110 exits power-save or sleep mode and detects that the TIM bit is set. In response, it sends a PS-Poll packet to the access point 120, as shown in block 510. As shown in block 520, the access point 120 then responds by transmitting a first "keep alive" message. As shown in block 525, the low-power Wi-Fi device 110 increments the number of "keep alive" messages it has transmitted since exiting sleep mode. If the "more data" bit is set (as shown in decision block 527), the low-power Wi-Fi device 110 transmits another PS-Poll packet (see block 510). This sequence repeats until the "more data" flag is no longer set. As shown in block 530, the low-power Wi-Fi device 110 then records the number of buffered "keep alive" messages (KAPackets). This value helps the low-power Wi-Fi device 110 determine the mode of operation going forward. This completes the process of characterizing the behavior of the access point 120. This therefore constitutes the actions performed in the learning state 300 .

[0033] Figure 5B A sequence that may be used by a low-power Wi-Fi device after performing the learning or characterization process is shown. As shown in block 540, the low-power Wi-Fi device 110 exits power-saving or sleep mode and detects that the TIM bit is set. In response, it checks to see the number of "keep-alive" packets typically sent by the access point 120, as determined during the learning or characterization process. Based on this value, the low-power Wi-Fi device 110 may modify its operation, as shown in decision block 545. For example, if the number of "keep-alive" messages is typically less than a threshold, which may be 2, for example, the low-power Wi-Fi device 110 may remain in its default operating state 310. In this default operating state, the low-power Wi-Fi device 110 transmits a PS-Poll packet to the access point 120, as shown in block 550. In response, the access point 120 transmits the buffered packet, as shown in block 555. This sequence repeats until the "more data" bit is no longer set, as shown in decision block 557. Thereafter, the low power Wi-Fi device 110 returns to the power save or sleep mode, as shown in block 560 .

[0034] However, if the typical number of "keep alive messages" is not less than a predetermined threshold, the low power Wi-Fi device 110 may modify its operation, as shown in block 570. In this modified operational state 320, the low power Wi-Fi device may transmit a packet with PM=0 to the access point 120, indicating that it is active, as shown in block 580. This may be a NULL packet, a QOS NULL packet, a data packet, or a QOS data packet. In response, the access point 120 will begin transmitting buffered packets without requiring the low power Wi-Fi device 110 to transmit multiple PS-Poll packets, as shown in block 585. Once the last packet is received by the low power Wi-Fi device 110, the low power Wi-Fi device 110 transmits a packet with PM=1, as shown in block 590, and returns to power saving or sleep mode.

[0035] Therefore, when the low-power Wi-Fi device determines that the behavior of the access point 120 is such that multiple packets will have been buffered when the low-power Wi-Fi device 110 exits sleep mode, it can modify its operation to exit the legacy power management mode so that it does not have to transmit multiple PS-Poll packets. In addition, this approach can also be used to reduce the total time that the low-power Wi-Fi device 110 is not in sleep mode. Note that this is the same modified behavior that occurs when the low-power Wi-Fi device 110 determines that the access point 120 is not responding to PS-Poll packets.

[0036] A third example of modified operation based on access point 120's behavior involves aggregation. Aggregation is a feature that allows two or more data frames to be sent as a single transmission. This feature reduces overhead because multiple packets share a common PHY header, reduces the number of medium accesses (one access per frame), and reduces acknowledgment latency and acknowledgment times. To establish aggregation, the access point and low-power Wi-Fi device must negotiate various parameters, such as the maximum number of data frames in a single transmission. These parameters are collectively referred to as the aggregation context. Unfortunately, some access points may delete the aggregation context when the low-power Wi-Fi device enters power-saving or sleep mode. Then, when access point 120 has data to transmit to low-power Wi-Fi device 110, it sets the TIM bit. Subsequently, upon receiving a PS-Poll packet, the access point may attempt to establish the aggregation context. This results in multiple transmissions and receptions of frames before the actual data frames are transmitted. When a low-power Wi-Fi device expects to send a small amount of data after a long interval, known as occasional data (e.g., for a door lock), these established aggregation contexts are destroyed and re-established the next time. These extra transmissions and receptions drain the battery.

[0037] Thus, low power Wi-Fi device 110 may modify its operation based on the aggregated context requested by access point 120 . Figure 6 First, as shown in block 600, the low power Wi-Fi device 110 may observe the number of TIDs (traffic identifiers) for which the access point 120 has requested an aggregated context. As shown in block 610, the low power Wi-Fi device 110 may also associate an aggregation with the data type on each TID.

[0038] Based on this information, the low-power Wi-Fi device 110 can take different actions. As shown in block 620, if the aggregate context TID is set only for TIDs on which the low-power Wi-Fi device 110 has continuous or bursty data, the low-power Wi-Fi device 110 can enter the default operating state 310 and establish an aggregate context. However, if the aggregate context is set for TIDs on which the low-power Wi-Fi device 110 has occasional data and other TIDs, the low-power Wi-Fi device 110 can enter the modified operating state 320 and ignore or deny the request to set the aggregate context and send a packet with PM=0 to the access point 120, as shown in block 630. This packet can be a NULL packet, a QOS NULL packet, a data packet, or a QOS data packet. This will allow the low-power Wi-Fi device 110 to retrieve the data, but will not establish any aggregate context, thereby reducing transmissions.

[0039] Note that Figure 3 As shown in FIG, if the low-power Wi-Fi device 110 is disconnected from the access point, the observations and modifications made by the low-power Wi-Fi device may be deleted. This disconnection may occur for a variety of reasons. For example, the low-power Wi-Fi device may leave the basic service set (BSS) of the access point 120. Alternatively, the access point 120 may have been offline, for example, to receive a software update.

[0040] In the first scenario, the observations made by the low-power Wi-Fi device about access point 120 remain valid. Therefore, in certain embodiments, low-power Wi-Fi device 110 may save the last timestamp it received from access point 120. This may be contained in the TSF field of the beacon. The low-power Wi-Fi device can then calculate the time it was outside of access point 120's BSS, referred to as the "away time." When it returns to access point 120's BSS, it calculates the expected timestamp by adding the last received timestamp and the away time. If the TSF field received in the next beacon from the access point is within the expected range, the low-power Wi-Fi device may save all of its previously learned information about access point 120. However, if the TSF field received in the next beacon is outside the expected range, low-power Wi-Fi device 110 may forget its learned behavior and return to learning state 300, restarting characterization.

[0041] This system and method has numerous advantages. By tracking the behavior of access points, low-power Wi-Fi devices can reduce their power consumption in several ways. First, it can reduce the number of packets transmitted but not acted upon. Second, it can reduce the number of PS-Poll packets in situations where a large number of buffered packets is expected. Third, in some cases, it can reduce transmissions by limiting aggregation.

[0042] The present disclosure is not limited in scope by the specific embodiments described herein. In fact, in addition to those described herein, various other embodiments and modifications of the present disclosure will be apparent to those of ordinary skill in the art based on the foregoing description and drawings. Therefore, such other embodiments and modifications are intended to fall within the scope of the present disclosure. In addition, although the present disclosure has been described herein in the context of a specific implementation in a specific environment for a specific purpose, those of ordinary skill in the art will recognize that its usefulness is not limited thereto, and the present disclosure can be beneficially implemented in any number of environments for any number of purposes. Therefore, the claims set forth below should be interpreted according to the full scope and spirit of the present disclosure as described herein.

Claims

1. A method of operating a low-power Wi-Fi device, comprising: observing behavior of an access point when the low-power Wi-Fi device is in a default operating state; as well as If the behavior differs from expected behavior, operation of the low power Wi-Fi device is modified to reduce transmission or power consumption.

2. The method according to claim 1, wherein The low power Wi-Fi device observes the access point's response to the PS-Poll message.

3. The method according to claim 2, wherein: If the access point does not respond to a PS-Poll message, the low power Wi-Fi device modifies the operation by transmitting packets with a power management (PM) bit set to 0 or 1 to indicate when the low power Wi-Fi device is in active mode and power save mode, respectively.

4. The method according to claim 3, wherein: The packet transmitted with the PM bit set to 0 or 1 is a NULL packet, a QOS NULL packet, a data packet or a QOS data packet.

5. The method according to claim 1, wherein When the low power Wi-Fi device is in a power save or sleep mode, the low power Wi-Fi device observes the number of “keep alive” messages transmitted by the access point.

6. The method according to claim 5, wherein: If the number of Keep Alive messages is less than a predetermined threshold, the low power Wi-Fi device utilizes a PS-Poll message.

7. The method according to claim 5, wherein: If the number of Keep Alive messages is greater than a predetermined threshold, the low power Wi-Fi device modifies the operation by transmitting packets with a power management (PM) bit set to 0 to indicate that the low power Wi-Fi device is in active mode.

8. The method of claim 1, wherein: The low power Wi-Fi device observes the number and type of TIDs (Traffic Identifiers) for which aggregated context is requested by the access point.

9. The method of claim 8, wherein: If the low power Wi-Fi device has continuous or bursty data associated with the TID, it establishes the aggregated context.

10. The method of claim 8, wherein: If the low power Wi-Fi device has occasional data associated with the TID, the low power Wi-Fi device modifies the operation by denying the request and transmitting a packet with a power management (PM) bit set to 0 to indicate that the low power Wi-Fi device is in active mode.

11. The method of claim 1 , further comprising exiting the modified mode of operation after a predetermined amount of time or a predetermined number of packets and repeating the observing.

12. The method of claim 1, further comprising exiting a modified mode of operation and repeating the observing if the connection between the low power Wi-Fi device and the access point is terminated.

13. A low-power Wi-Fi device, comprising: Wi-Fi network interface; processing unit; as well as a memory device in communication with the processing unit, comprising instructions that, when executed by the processing unit, enable the low-power Wi-Fi device to: observing behavior of an access point when the low-power Wi-Fi device is in a default operating state; as well as If the behavior differs from expected behavior, operation of the low power Wi-Fi device is modified to reduce transmission or power consumption.

14. The low-power Wi-Fi device of claim 13, wherein: The low power Wi-Fi device observes the access point's response to the PS-Poll message.

15. The low-power Wi-Fi device of claim 14, wherein: The memory device also includes instructions that enable the low power Wi-Fi device to: If the access point does not respond to a PS-Poll message, the operation is modified by transmitting packets with a power management (PM) bit set to 0 or 1 to indicate when the low power Wi-Fi device is in active mode and power save mode, respectively.

16. The low-power Wi-Fi device of claim 13, wherein: When the low power Wi-Fi device is in a power save or sleep mode, the low power Wi-Fi device observes the number of “keep alive” messages transmitted by the access point.

17. The low-power Wi-Fi device of claim 16, wherein: The memory device also includes instructions that enable the low power Wi-Fi device to: If said number of "Keep Alive" messages is less than a predetermined threshold, transmitting a PS-Poll message; and If the number of Keep Alive messages is equal to or greater than the predetermined threshold, a packet is transmitted with a power management (PM) bit set to 0 to indicate that the low power Wi-Fi device is in active mode.

18. The low-power Wi-Fi device of claim 13, wherein: The low power Wi-Fi device observes the number and type of TIDs (Traffic Identifiers) for which aggregated context is requested by the access point.

19. The low power Wi-Fi device of claim 18, wherein: The memory device also includes instructions that enable the low power Wi-Fi device to: establishing the aggregated context if the low power Wi-Fi device has continuous or bursty data associated with the TID; as well as If the low power Wi-Fi device has occasional data associated with the TID, the request is denied and the packet is transmitted with a power management (PM) bit set to 0 to indicate that the low power Wi-Fi device is in active mode.

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