A roaming control method based on a mesh network

Abstract

The present application mainly relates to the field of wireless device roaming, in order to solve the problem that the roaming of the device based on the multi-AP Mesh network is mainly based on the single index of RSSI to make the decision, and the misjudgment is easily caused under the factors such as the large environmental interference or the poor performance of the terminal antenna; the core idea is that: firstly, the Mesh network is configured, and the master and slave APs are determined; the STA terminal associates with a slave AP in the Mesh network, i.e. AP1, the association information of the STA terminal is notified to the master AP, and whether the STA terminal enters the standby roaming decision state is determined by the RSSI of the STA terminal and the packet loss rate of the packet sent by AP1 to the STA terminal; AP1 continuously measures the wireless air interface packet rate of the STA terminal in multiple periods and the corresponding air interface message times to calculate the weighted average rate, compares the weighted average rate with the highest rate negotiated by the STA terminal and AP1, and judges whether the STA terminal meets the condition of entering the roaming decision state; after the STA terminal enters the roaming decision state, the destination AP of roaming is selected according to the RSSI of the STA terminal, the self acoustic channel load of the AP and the bottom noise, and the destination AP is connected.

Description

Technical Field

[0001] This invention relates primarily to the field of wireless device roaming, and in particular to a roaming control method based on a mesh network. Background Technology

[0002] With the widespread adoption of home wireless networks, the acceleration of fiber optic networks, and the increasing number of smart devices accessing the internet via access points (APs), the coverage of a single AP is often limited. Mesh networking has emerged to address this need. Mesh distributed routing generates a mesh network through networking, which can be achieved through wired direct-plug networking or wireless networking. Mesh networking with multiple APs greatly expands the signal coverage. For device roaming in a mesh environment, decisions are mainly based on the single metric RSSI. However, RSSI can be prone to misjudgment due to factors such as significant environmental interference or poor terminal antenna performance. Summary of the Invention

[0003] The technical problem to be solved by this invention:

[0004] A roaming control method based on mesh networks is proposed to address the problem that roaming decisions for devices in multi-AP mesh networks are mainly based on a single RSSI indicator, which can easily lead to misjudgments under conditions of high environmental interference or poor terminal antenna core performance.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0006] A roaming control method based on a mesh network includes the following steps:

[0007] Step 1: Configure the Mesh network, determine the master and slave APs, and ensure that there is at least one slave AP;

[0008] Step 2: Associate the STA terminal with one of the APs in the Mesh network, denoted as AP1. AP1 announces the STA terminal's information to the master AP, and AP1 continuously records the STA terminal's RSSI.

[0009] Step 3: AP1 determines whether to enter the roaming decision state based on the RSSI of the STA terminal and the packet loss rate of the broadcast packets it sends to the STA terminal;

[0010] Step 4: After the STA terminal enters the roaming decision state, AP1 continuously measures the STA terminal's wireless air interface packet rate and the corresponding number of air interface messages for multiple measurement cycles to determine whether to enter the roaming decision state.

[0011] Step 5: After the STA terminal enters the roaming decision state, AP1 sends a roaming announcement to the master AP. Upon receiving the announcement, the master AP initiates roaming measurement and notifies all slave APs to perform roaming measurement. The measurement continues for multiple cycles. The master AP summarizes the measurement results of all APs and selects the destination AP for the STA terminal to roam. If the STA terminal is connected to the master AP, the master AP directly initiates roaming measurement and notifies the other slave APs to initiate roaming measurement.

[0012] Step 6: The STA terminal establishes a connection with the destination AP.

[0013] Furthermore, the method for determining whether to enter the roaming decision state in step 3 specifically includes: calculating the average RSSI of the STA terminal over multiple measurement periods. avg The packet loss rate ratio between AP1 and STA terminals when sending broadcast packets. pkt_loss If either of the following two conditions is met, the STA terminal enters the roaming decision-making state.

[0014] 1) Average RSSI avg RSSI less than the set RSSI threshold thres1 Furthermore, the packet loss rate ratio when AP1 sends packets to the STA terminal is... pkt_loss Greater than the set packet loss rate threshold Ratio pkt_loss_thres ;

[0015] 2) The average RSSI value (RSSIavg) is less than the set RSSI threshold. thres2 .

[0016] Furthermore, step 4, determining whether the STA terminal has entered the roaming decision state, specifically includes the following steps: After the STA terminal enters the roaming decision state, AP1 continuously measures the radio air interface packet rate of the STA terminal within multiple measurement periods. Based on the radio air interface packet rate and the number of air interface messages corresponding to the radio air interface packet, a weighted average rate is calculated. The weighted average rate is compared with the highest rate negotiated between the STA terminal and AP1. If the weighted average rate is less than a certain proportion of the highest rate and the conditions for any STA terminal to enter the roaming decision state are met, then the STA terminal enters the roaming decision state; otherwise, it returns to the initial state.

[0017] Furthermore, the specific method for selecting the destination AP that the STA terminal needs to roam in step 5 includes:

[0018] 1) Select the M APs with the largest mean RSSI of the STA terminal as the target AP set for the first round of screening, including AP1;

[0019] 2) Calculate the ratio of the maximum rate that the above M APs can support for the STA terminal to the inherent maximum rate of the STA terminal, and select the N APs with the largest ratio;

[0020] 3) Collect the channel load and noise floor values ​​measured by each of the above N APs, and calculate the interference factor value according to the weight of the channel load and noise floor values; if the AP supports dual-band merging, calculate the interference factor for each frequency band as an independent AP.

[0021] 4) Based on the number of STA terminals already connected to the AP and the quick calculation factor corresponding to the bandwidth supported by the AP, calculate the terminal load factor value (Road) for each of the N APs. endpoint = α * Num endpoint； If the AP supports dual-band merging, each frequency band will be treated as an independent AP and the terminal load factor will be calculated separately.

[0022] 5) Sort the sum of all frequency band interference factor values ​​and terminal load factor values ​​of all APs, and select the AP with the smallest sum as the first target AP; where:

[0023] If the first target AP is in the same frequency band as the existing frequency band of the STA terminal, then the first target AP is taken as the final destination AP, that is, AP1 is taken as the destination AP;

[0024] If the first target AP and the STA terminal are not on the same frequency band, the AP with the smallest sum of interference factor value and terminal load factor value on the same frequency band as the STA terminal is taken as the second target AP, and AP1 is taken as the first target AP; at this time, the target AP still needs to be determined according to the specific roaming action.

[0025] Furthermore, the connection method between the STA terminal and the destination AP described in step 6 specifically includes:

[0026] If the destination AP is AP1, the master AP sends a roaming announcement to all APs, informing them of the MAC addresses of the destination AP and the STA terminal. AP1 then sends a BTM request to the STA terminal based on whether the STA terminal supports the IEEE 802.11kv communication protocol, and connects to the destination AP.

[0027] If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal receives the BTM request from AP1, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist.

[0028] If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal rejects the BTM request from AP1, then the roaming process will be terminated.

[0029] If the STA terminal does not support the IEEE E802.11kv communication protocol, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist. AP1 initiates the Deauth procedure.

[0030] If the AP with the smallest sum of interference factor and terminal load factor in the same frequency band as the STA terminal is selected as the second target AP, and AP1 is selected as the first target AP; firstly, the first target AP is set as the destination AP, and the main AP sends a roaming announcement to all APs; AP1 sends a BTM request to the STA terminal according to whether the STA terminal supports the IEEE E802.11kv communication protocol, and connects to the destination AP;

[0031] If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal receives the BTM request from AP1, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist.

[0032] If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal rejects the BTM request of AP1, switch the target AP to the second target AP and try to connect again;

[0033] If the STA terminal does not support the IEEE E802.11kv communication protocol, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist. AP1 initiates the Deauth procedure.

[0034] The beneficial effects of this invention are:

[0035] The roaming control method based on Mesh networks described in this invention selects the target AP based on multiple factors such as the STA terminal's RSSI, packet loss rate, wireless air interface packet rate, channel load, and noise floor value, thereby improving the accuracy and necessity of roaming decisions and optimizing the user's internet experience. Attached Figure Description

[0036] Figure 1 This is a flowchart of a roaming control method based on a Mesh network as described in this invention.

[0037] Figure 2 This is a flowchart of a roaming control method based on a Mesh network according to an embodiment of the present invention. Detailed Implementation

[0038] The roaming control method based on a mesh network described in this invention, such as Figure 1As shown, firstly, a mesh network is configured, and master and slave APs are determined. The STA terminal associates with a slave AP in the mesh network, denoted as AP1, and announces the STA terminal's association information to the master AP. AP1 continuously records the STA terminal's RSSI. Firstly, it determines whether the STA terminal should enter the roaming decision-making state based on the STA terminal's RSSI and the packet loss rate of the broadcast packets sent by AP1 to the STA terminal. After the STA terminal enters the roaming decision-making state, AP1 continuously measures the STA terminal's radio interface packet rate over multiple measurement periods, calculates the weighted average rate, and compares the weighted rate with the highest rate negotiated between the STA terminal and AP1 to determine if the STA terminal meets the conditions for entering the roaming decision-making state. After entering the roaming decision-making state, the STA terminal selects the roaming destination AP based on its RSSI, the AP's own acoustic channel load, and noise floor, and connects to the destination AP.

[0039] Example:

[0040] like Figure 2 As shown, firstly, a Mesh network is configured, which contains multiple APs. All APs have the same SSID, encryption method, and key. One AP is connected to the external network to be designated as the master AP. The other slave APs are networked with the master AP through the Mesh network, and the number of slave APs is greater than or equal to 1.

[0041] The STA terminal connects to an AP in the Mesh network, denoted as AP1. AP1 announces the association information of the STA terminal to the main AP, which includes the frequency band, negotiation rate, maximum supported rate of the frequency band, and whether it supports the 802.11kv communication protocol.

[0042] AP1 continuously records the RSSI of the STA terminal at a certain period (default is 5s) and marks it as the initial state.

[0043] AP1 makes an initial roaming decision based on the STA terminal's RSSI and the packet loss rate of its own broadcast packets to the STA terminal. It calculates the average RSSI of the STA terminal over several consecutive periods (default is 5) and the packet loss rate of AP1's packets to the STA terminal. If one of the following conditions is met, the STA terminal enters the roaming decision state:

[0044] 1. Average RSSI avg RSSI less than the set RSSI threshold thres1 (Default is -75dBm), and the packet loss rate Ratio when AP1 sends packets to the STA terminal. pkt_loss Greater than the set packet loss rate threshold Ratio pkt_loss_thres (Default is 65%).

[0045] 2. Average RSSIavg RSSI less than the set RSSI threshold thres2 (Default is -82dBm).

[0046] After the STA terminal enters the roaming decision-making state, AP1 continuously measures the STA terminal's air interface packet rate for J (default 4) measurement cycles (cycle T=5s), calculates the weighted average rate, and compares the weighted average rate with the highest wireless rate negotiated between the STA terminal and AP1. If the ratio of the weighted average rate to the highest wireless rate is less than a certain value (default 35%), and the conditions for entering the roaming decision-making state are met within the current J measurement cycles, then the STA terminal enters the roaming decision-making state; otherwise, it returns to the initial state.

[0047] After entering the roaming decision state, AP1 sends a roaming measurement announcement to the master AP (which can also be AP1 itself). Upon receiving the announcement, the master AP initiates its own roaming measurement and notifies the slave APs to perform roaming measurements. The measurement is performed continuously for K cycles (K defaults to 5 cycles, with each cycle lasting 3 seconds). The roaming measurement metrics include the RSSI of the STA terminal, the channel load value of the AP itself, and the noise floor value. After the measurement is completed, the master AP summarizes the measurement results of all APs and selects the target AP that the STA terminal needs to roam to.

[0048] The specific method for determining the destination AP for STA terminal roaming is based on the following algorithm:

[0049] Select the M (M≥2) APs with the largest RSSI values ​​of the STA terminal as the first round target AP set (including AP1 associated with the current STA terminal itself).

[0050] Calculate the ratio of the maximum rate that the M APs can support for the STA terminal to the maximum rate of the STA terminal, and perform a secondary screening based on the ratio from largest to smallest to select the candidate AP with the largest ratio among N (2≤N≤M).

[0051] Collect the channel load and noise floor values ​​measured by each of the N APs. If the AP supports dual-band merging, the measurement data of the two frequency bands of this AP are required. The interference factor value is obtained by calculating the two variables of channel load and noise floor value according to a specific weighting (channel load weight 2 / 3, noise floor weight 1 / 3).

[0052] Based on the number of STA terminals already connected to the AP, calculate the terminal load factor value (Load = Road) for each of the N APs. endpoint = α * Num endpoint， Different calculation factors (generally α) are determined based on the bandwidth supported by the AP. 2.4G ≥X* α 5G(X≥4), if the AP supports dual-band merging, then the terminal load factor values ​​for both frequency bands of this AP are required.

[0053] The interference factor values ​​of all APs across all frequency bands, plus the terminal load factor value, are sorted from smallest to largest according to their respective weights (the interference factor value is weighted at 3 / 5 and the terminal load factor value at 2 / 5 by default). The AP with the smallest calculated result is taken as the first target AP. If the AP supports dual-band merging, the obtained interference factor value and terminal load factor value are the two frequency bands of the AP, and each frequency band is treated as an independent AP.

[0054] If the first target AP is in the same frequency band as the existing frequency band of the STA terminal, then the first target AP is the destination AP;

[0055] If the first target AP and the STA terminal are not on the same frequency band, the AP that is on the same frequency band as the STA terminal and has the smallest sum of interference factors and terminal load is selected as the second target AP. In this case, the target AP still needs to be determined based on the specific roaming action.

[0056] If the primary target AP and the STA terminal are on the same frequency band, the primary AP sends a roaming initiation notice to all APs, informing them of the MAC address of the target AP and the MAC address of the STA terminal. The target AP prepares to accept the STA terminal association initiation process, and the associated AP (AP1) prepares to guide the STA terminal roaming flow. Depending on whether the STA terminal supports the 802.11kv communication protocol, the specific roaming action is determined according to the following algorithm:

[0057] 1) If the STA terminal supports the 802.11kv communication protocol, AP1 sends a BTM request to the STA terminal. If the STA terminal accepts the request, AP1 notifies the master AP that the STA terminal has accepted the BTM request. The master AP notifies the destination AP to start a timer (default 40s) to wait for the STA terminal to associate. The master AP notifies other APs that are not the destination AP to add this STA terminal to the timer (default 45s) blacklist.

[0058] 2) If the STA terminal supports the 802.11kv communication protocol, AP1 sends a BTM request to the STA terminal. If the STA terminal rejects the request, AP1 notifies the main AP that the STA terminal has rejected the BTM request and exits the roaming process.

[0059] 3) If the STA terminal does not support the 802.11kv communication protocol, the AP notifies the destination AP to start a timer (default 40s) to wait for the STA terminal to associate. The main AP notifies other APs to add this STA terminal to the timer (default 45s) blacklist. Then AP1 initiates the Deauth process. After the timeout, the STA terminal has not been associated with the destination AP.

[0060] If 1) and 3) fail to connect to the destination AP after the default waiting time, the main AP sends a roaming failure notification to all other APs, informing the STA terminal to connect to the original AP1's MAC address and the STA terminal's MAC address. The original AP1 is ready to accept the STA terminal's association initiation process, and other APs start a timed (default 45s) blacklist.

[0061] If the AP with the smallest sum of interference factor and terminal load factor in the same frequency band as the STA terminal is selected as the second target AP, and AP1 is selected as the first target AP; the first target AP is selected as the destination AP, and the primary AP sends a roaming initiation notice to all APs, informing them of the MAC address of the destination AP and the MAC address of the STA terminal. The destination AP is ready to accept the STA terminal association initiation process, and the associated AP (AP1) is ready to guide the STA terminal roaming flow. Depending on whether the STA terminal supports the 802.11kv communication protocol, the specific roaming action is determined according to the following algorithm:

[0062] 1) If the STA terminal supports the 802.11kv communication protocol, AP1 sends a BTM request to the STA terminal. If the STA terminal accepts the request, AP1 notifies the master AP that the STA terminal has accepted the BTM request. The master AP notifies the destination AP to start a timer (default 40s) to wait for the STA terminal to associate. The master AP notifies non-destination APs to add this STA terminal to the timer (default 45s) blacklist.

[0063] 2) If the STA terminal supports the 802.11kv communication protocol, AP1 sends a BTM request to the STA terminal. If the STA terminal rejects the request, AP1 notifies the main AP that the STA terminal has rejected the BTM request, switches the second target AP as the destination AP, and proceeds with the subsequent process according to the method described in h.

[0064] 3) If the STA terminal does not support the 802.11kv communication protocol, the AP notifies the destination AP to start a timer (default 40s) to wait for the STA terminal to associate. The main AP notifies other APs to add this STA terminal to the timer (default 45s) blacklist. Then AP1 initiates the Deauth process.

[0065] If 1) and 3) fail to connect to the destination AP after the timeout, the main AP sends a roaming failure notification to all APs, informing the STA terminal to connect to the original AP1's MAC address and the STA terminal's MAC address. The original AP1 is ready to accept the STA terminal's association initiation process, and other APs open a timed blacklist.

Claims

1. A roaming control method based on a mesh network, characterized in that, Includes the following steps: Step 1: Configure the Mesh network, determine the master and slave APs, and ensure that there is at least one slave AP; Step 2: Associate the STA terminal with one of the APs in the Mesh network, denoted as AP1. AP1 announces the STA terminal's information to the master AP, and AP1 continuously records the STA terminal's RSSI. Step 3: AP1 determines whether the STA terminal should enter the roaming decision state based on the STA terminal's RSSI and the packet loss rate of the broadcast packets it sends to the STA terminal; Step 4: After the STA terminal enters the roaming decision-making state, AP1 continuously measures the STA terminal's radio air interface packet rate and the corresponding number of air interface messages for multiple measurement periods to determine whether to enter the roaming decision-making state. Specifically, after the STA terminal enters the roaming decision-making state, AP1 continuously measures the STA terminal's radio air interface packet rate within multiple measurement periods. Based on the radio air interface packet rate and the corresponding number of air interface messages, a weighted average rate is calculated. The weighted average rate is compared with the highest rate negotiated between the STA terminal and AP1. If the weighted average rate is less than a certain percentage of the highest rate and the conditions for any STA terminal to enter the roaming decision-making state are met, then the STA terminal enters the roaming decision-making state; otherwise, it returns to the initial state. Step 5: After the STA terminal enters the roaming decision state, AP1 sends a roaming announcement to the master AP. Upon receiving the announcement, the master AP initiates roaming measurement and notifies all slave APs to perform roaming measurement. After continuous measurement for multiple cycles, the master AP summarizes the measurement results of all APs and selects the target AP for the STA terminal to roam. Step 6: The STA terminal establishes a connection with the destination AP.

2. The roaming control method based on a mesh network according to claim 1, characterized in that, Step 3, the method for determining whether to enter the roaming decision state, specifically includes: calculating the average RSSI of the STA terminal over multiple measurement periods. avg The packet loss rate ratio between AP1 and STA terminals when sending broadcast packets. pkt_loss If either of the following two conditions is met, the STA terminal enters the roaming decision-making state. 1) Average RSSI avg RSSI less than the set RSSI threshold thres1 Furthermore, the packet loss rate ratio when AP1 sends packets to the STA terminal is... pkt_loss Greater than the set packet loss rate threshold Ratio pkt_loss_thres ; 2) The average RSSI value (RSSIavg) is less than the set RSSI threshold. thres2 .

3. The roaming control method based on a mesh network according to claim 1, characterized in that, Step 5 describes the specific method for selecting the destination AP that the STA terminal needs to roam to, which includes: 1) Select the M APs with the largest mean RSSI of the STA terminal as the target AP set for the first round of screening, including AP1; 2) Calculate the ratio of the maximum rate that the above M APs can support for the STA terminal to the inherent maximum rate of the STA terminal, and select the N APs with the largest ratio; 3) Collect the channel load and noise floor values ​​measured by each of the above N APs, and calculate the interference factor value according to the weight of the channel load and noise floor values; if the AP supports dual-band merging, calculate the interference factor for each frequency band as an independent AP. 4) Calculate the terminal load factor value (Road) for each of the N APs based on the number of STA terminals already connected to the AP and the quick calculation factor corresponding to the bandwidth supported by the AP. endpoint = α * Num endpoint； If the AP supports dual-band merging, each frequency band will be treated as an independent AP and the terminal load factor will be calculated separately. 5) Sort the sum of the interference factor values ​​and terminal load factor values ​​of all APs across all frequency bands according to the respective weights of interference factors and terminal load factors, and select the AP with the smallest sum as the first target AP; where: If the first target AP is in the same frequency band as the existing frequency band of the STA terminal, then the first target AP is taken as the final destination AP, that is, AP1 is taken as the destination AP; If the first target AP and the STA terminal are not on the same frequency band, the AP with the smallest sum of interference factor value and terminal load factor value on the same frequency band as the STA terminal is taken as the second target AP, and AP1 is taken as the first target AP; at this time, the target AP still needs to be determined according to the specific roaming action.

4. The roaming control method based on a mesh network according to claim 3, characterized in that, Step 6 describes the method for connecting the STA terminal to the destination AP, which specifically includes: If the destination AP is AP1, the master AP sends a roaming announcement to all APs, informing them of the MAC addresses of the destination AP and the STA terminal. AP1 then sends a BTM request to the STA terminal based on whether the STA terminal supports the IEEE 802.11kv communication protocol, and connects to the destination AP. If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal receives the BTM request from AP1, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist. If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal rejects the AP1's BTM request, then the roaming process will be terminated. If the STA terminal does not support the IEEE E802.11kv communication protocol, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist. AP1 initiates the Deauth procedure. If the AP with the lowest interference factor and terminal load factor in the same frequency band as the STA terminal is selected as the second target AP, and AP1 is selected as the first target AP; firstly, the first target AP is set as the destination AP, and the main AP sends a roaming announcement to all APs; AP1 sends a BTM request to the STA terminal according to whether the STA terminal supports the IEEE E802.11kv communication protocol, and connects to the destination AP; If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal receives the BTM request from AP1, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist. If the STA terminal supports the IEEE 802.11kv communication protocol and the STA terminal rejects AP1's BTM request, switch the target AP to the second target AP and try to connect again; If the STA terminal does not support the IEEE E802.11kv communication protocol, the master AP notifies the destination AP to start a timed wait for the STA terminal to associate, and notifies non-destination APs to add this STA terminal to the timed blacklist. AP1 initiates the Deauth procedure.

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