KR20130109420A - Access point supporting 2.4ghz/5ghz dual band in wireless lan and road balancing method thereof - Google Patents

Abstract

PURPOSE: An access point supporting dual bands in a wireless local area network (WLAN) and a method for dispersing load thereof are provided to enable only a band having relatively low load of the dual bands to transmit a probe response frame even when there is a probe request from a new WLAN terminal to access. CONSTITUTION: A band load calculation unit (120) calculates load state per band for dual bands of a WLAN band at every established period. The band load calculation part judges whether the calculated load per band is equal to or above a preestablished threshold. When the calculated load per band is equal to or above the preestablished threshold, an access management part transmits a probe response frame as to the probe request frame of a WLAN terminal to access newly in a band having relatively low load. The access management unit does not transmit the probe response frame as to the probe request frame of the WLAN terminal in a band having a relatively high load. [Reference numerals] (110) Access management unit; (120) Band load calculation unit; (130) Cycle setting unit; (AA) 2.4GHz band; (BB) 5GHz band

Description

ACCESS POINT SUPPORTING 2.4GHz / 5GHz DUAL BAND IN WIRELESS LAN AND ROAD BALANCING METHOD THEREOF}

The present invention relates to an access point supporting dual bands at the same time. In detail, an access point of a WLAN terminal is excessively concentrated from one access point supporting dual bands of 2.4 GHz frequency band and 5 GHz frequency band to one band. And an access point and load balancing method thereof for preventing traffic and effectively distributing traffic.

The WLAN service is a service for providing a service provided by existing short-range wired communication (wired LAN) using a wireless medium as a medium for data transmission.

The wireless LAN service is connected to a wireless LAN terminal such as a laptop, a personal digital assistant (PDA), a smart phone, an iPod, and the like, to an access point (AP) serving as a wired / wireless gateway. Service).

In order to use the WLAN service, the WLAN terminal first searches for an access point in the vicinity through a scan method and selects an access point to which the access point is to be connected from among the found access points.

In the scan method, a WLAN terminal transmits a probe request frame to all channels supported by the terminal, and if an access point exists in the corresponding channel, the access point transmits a probe response frame to access the probe request frame. This is done by notifying the presence of the point.

Therefore, an access point that simultaneously supports dual bands in an existing WLAN service transmits a probe response frame to the WLAN terminal for the dual band, and informs the WLAN terminal of the access point according to the wireless reception strength of the dual band. Select a band to try to connect.

However, according to the related art, when more WLAN terminals are connected to a specific band, or when a specific WLAN terminal uses much more data packets than other terminals, the load is concentrated in one of dual bands. This is because the user or the terminal of the WLAN terminal does not know which band has a high load, and thus the connection can be selected to a band having a high load. In this case, a WLAN terminal connected to a band having a high load has a problem of degrading quality compared to a WLAN terminal connected to another band, thereby slowing the transmission and reception of data.

The present invention has been made to solve the above problem, the access point calculates the load for the dual band supported by the access point every predetermined period, when the load exceeds the threshold request probe from a new WLAN terminal to connect Even if there is a (Probe Request), only the band having a relatively low load among the dual bands transmits a probe response frame, thereby preventing excessive concentration of access of the WLAN terminal in one band and effectively distributing traffic. The purpose of the present invention is to provide an access point and load balancing method thereof that can improve the quality of service.

To this end, according to the first aspect of the present invention, the access point of the present invention calculates the load state for each band for the dual band of the wireless LAN band for each preset period and whether the calculated load for each band is greater than or equal to a preset threshold. Band-specific load calculation unit for determining; And when the calculated load for each band is greater than or equal to a preset threshold, a band having a relatively low load transmits a probe response frame to a probe request frame of a WLAN terminal to be newly connected. The higher band may include a connection management unit for not transmitting a probe response frame for a probe request frame of the WLAN terminal.

The load calculation unit for each band may be configured to calculate the load for each band by combining one or more target conditions among the number of users of the dual band, data transmission amount, and packet retransmission rate.

In addition, the load calculation unit for each band is characterized by comparing the relative load according to the priority by giving priority to the target condition for calculating the load condition for each band.

According to a second aspect of the present invention, a load balancing method in an access point of the present invention includes the steps of: calculating, by the access point, a load condition for each band for each period of a dual band of a WLAN band; Determining whether the access point is equal to or greater than a predetermined threshold value for the band-specific load calculated by the access point; When the load condition for each band is greater than or equal to a preset threshold, a band having a low load with respect to a probe request frame of a WLAN terminal to which the access point newly connects transmits a probe response frame. The high load band may include non-probing a probe response frame with respect to a probe request frame of the WLAN terminal.

In the calculating of the band-specific loads for the dual band, one or more target conditions among the number of users of the dual band, the amount of data transmission, and the packet retransmission are combined.

The method may further include setting the predetermined period in the access point before calculating the load for each band.

According to the present invention, when a load occurs on an access point supporting dual bands simultaneously, the WLAN terminal to be newly connected automatically connects through a band having a relatively low load among the dual bands even if the load state for the dual band is unknown. By doing so, there is an effect of preventing excessive concentration of the connection of the WLAN terminal in one band.

In particular, when the load is calculated using the number of access points, transmission amount, retransmission rate, etc. of the WLAN terminal connected to the dual band, the number of the WLAN terminals connected to one band is small, but the load increases due to the high data transmission amount. Alternatively, traffic can be effectively distributed even when the load is high due to the high retransmission rate. As a result, data can be transmitted smoothly, thereby improving service quality and resolving user complaints.

In addition, even if the user of the WLAN terminal forcibly attempts to connect, it does not block the access and does not inform the existence of the access point. Therefore, load balancing may be performed without fear of generating a voice of customer (VOC).

1 is a diagram illustrating a configuration of a wireless LAN system to which an access point supporting dual bands of the present invention is applied.
2 is a diagram illustrating a configuration for load balancing in an access point supporting dual band of the present invention.
3 is a flow chart illustrating a method for load balancing in an access point supporting dual bands of the present invention.
4 is a flowchart illustrating a specific method of calculating the load of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The configuration of the present invention and the operation and effect thereof will be clearly understood through the following detailed description. Prior to the detailed description of the present invention, the same components will be denoted by the same reference numerals even if they are displayed on different drawings, and the detailed description will be omitted when it is determined that the well-known configuration may obscure the gist of the present invention. do.

1 is a diagram illustrating a configuration of a wireless LAN system to which an access point supporting dual bands of the present invention is applied.

The WLAN system according to the present invention prevents data traffic load from being concentrated in one of the bands between the access point 100 and the WLAN terminal 200 simultaneously supporting dual bands, thereby rapidly processing the WLAN terminal 200. Providing services to satisfy the demand for

In order to implement this, the plurality of WLAN terminals 200 searches for all the access points 100 present in the dual bands supported by the terminal, using a scanning method for detecting the presence of the accessible access point 100. A connection can be attempted to the access point. Alternatively, the plurality of WLAN terminals 200 may attempt to access a desired access point 100 using a method of directly inputting through a wireless set (SSID: Service Set IDentification) of the access point 100.

When the connection between each WLAN terminal 200 and the access point 100 is made, the WLAN terminal 200 transmits and receives various digital data through a dual band of the WLAN band supported by the access point 100.

Dual band refers to the 2.4GHz frequency band and 5GHz frequency band of the current wireless LAN band, but is not limited thereto and may be applied if there is a band capable of wireless LAN communication.

The WLAN terminal 200 may include a PC, a notebook computer, a tablet PC, a personal digital assistant (PDA), a smartphone, and the like.

The access point 100 simultaneously supports dual bands of a 2.4 GHz frequency band and a 5 GHz frequency band as a wireless LAN band.

In particular, in the access point 100 according to the present invention, when the load applied to the dual band is greater than or equal to a threshold value, a band of a relatively high load band among the dual bands is applied to a probe request of the WLAN terminal 200. Don't respond.

For example, when the number of WLAN terminals 200 connected to one of the dual bands is higher than the threshold 10, the access point 100 operates an algorithm for load balancing. Therefore, a band of a relatively high load band does not respond to a probe request transmitted from the WLAN terminal, and only a band of a low load band responds. Accordingly, load balancing is implemented by distributing the connection of the WLAN terminal to a low load band.

A detailed configuration of the access point 100 to implement this is shown in FIG.

Referring to FIG. 2, the access point 100 includes a connection manager 110, a load calculator 120 for each band, and a period setting unit 130.

The period setting unit 130 sets a period for calculating a load for the dual band. For example, the period is set to 1 minute, 3 minutes 5 minutes, and the like and can be changed as necessary.

The band-specific load calculator 120 calculates a band-specific load state for the dual band for each period previously set by the period setting unit 130. Then, it is determined whether the calculated load state for each band is equal to or more than a preset threshold. The preset threshold may vary depending on the method of calculating the load. For example, in the case of the calculation method using the number of accessors, the threshold may be a limit value for the number of accessors, and in the case of the calculation method using the data transmission amount, it may be a threshold value for the average data transmission rate.

The method of calculating the load for each band may use the number of users of each dual band, the amount of data transmission, and the amount of packet retransmission.

The calculation method using the number of accessors is a method of determining a load by comparing the number of WLAN terminals connected to each of the dual bands. For example, if 12 wireless LAN terminals are connected to the 2.4 GHz frequency band and 15 wireless LAN terminals are connected to the 5 GHz frequency band, the load calculation unit 120 for each band uses the 5 GHz frequency through comparison of the number of accessors. It can be determined that the load of the band is relatively high.

The calculation method using the data transmission amount is a method of detecting an average data transmission amount by analyzing packets received in each of the dual bands, comparing the detected two average data transmission amounts, and determining that a load having a relatively high average data transmission amount is high. For example, when the average data transmission amount is 5 Mbps in the band of the 2.4 GHz band and the average data transmission amount is 3 Mbps in the band of the 5 GHz band, the load calculation unit 120 for each band performs a 2.4 GHz frequency through comparison between the average data transmission amounts. It can be determined that the load of the band is relatively high.

Next, the calculation method using the packet retransmission amount is a method of determining that a band having a relatively high retransmission rate is high by analyzing packets received in each of the dual bands and comparing the average retransmission rate. If the average packet retransmission ratio of the 2.4 GHz frequency band is 10%, and the average packet retransmission ratio of the 5 GHz frequency band is 5%, the load calculation unit 120 for each band is relatively loaded with the 2.4 GHz frequency band based on the above scheme. It can be judged higher.

As such, the load calculator 120 for each band may determine the load state using only one calculation method among the number of accessors, the data transmission amount, and the packet retransmission rate, or may determine the combination of two or more calculation methods. In this case, the load calculation unit 230 for each band may determine the load according to the priority by giving priority to each calculation method. For example, the calculation method using the data transmission amount is set as the first priority, and the calculation method using the number of accessors is set as the second priority, so that the load may be calculated to be high when the number of accessors is small but the data transmission amount is high.

The connection manager 110 receives a probe request frame transmitted from the WLAN terminal when the WLAN terminal is scanned, and transmits a probe response frame to the probe request frame. By transmitting to the interface between the wireless LAN terminal and the access point.

In addition, the access management unit 100 receives a frame for an authentication request from the wireless LAN terminal when the wireless LAN terminal is to be connected after a scan of the wireless LAN terminal or through an access point wireless set (SSID: Service Set IDentification), and receives An authentication response frame may be transmitted to the WLAN terminal with respect to one authentication request frame.

At this time, the connection manager 110 transmits a probe response frame in a dual band or a band having a low load according to the load state calculated by the load calculation unit 120 for each band.

When the load for each band calculated by the load for each load calculation unit 120 is smaller than the threshold, the connection manager 110 may transmit a probe response frame through the dual band.

On the contrary, when the load of each band calculated by the load calculation unit 120 is greater than or equal to a threshold value, the connection manager 100 transmits a probe response frame through a band having a lower load among the dual bands, and is relatively Higher load bands do not send probe response frames.

Here, the non-probe of the probe response frame means that no response is made to the probe request frame transmitted from the WLAN terminal, and that the WLAN terminal is not informed of the existence of the access point (SSID information). . Therefore, when the WLAN terminal searches for an adjacent access point existing around, only the access point of the band that does not recognize the access point of the band that does not respond to the probe request frame is not recognized.

According to this operation, the access point of the present invention calculates the load of each band at regular intervals, and when the load is greater than or equal to a threshold, the access point of the present invention does not respond to a probe request of a WLAN terminal to which a relatively high load band is newly connected. By not doing so, the connection of the WLAN terminal for a predetermined period of time is induced to a low load band. Thus, the load on the access point is distributed.

Hereinafter, the process of distributing the load in the access point of the present invention based on the above configuration will be described in detail.

3 is a flowchart illustrating a method of distributing load in an access point supporting dual bands of the present invention, and FIG. 4 is a flowchart illustrating a specific method of calculating a load of the present invention.

First, referring to FIG. 3, the AP sets a predetermined period for calculating the load of the WLAN band (S100). The period can be set to 1 minute, 3 minutes, 5 minutes, or the like, and can be changed according to the communication environment or the capacity of the access point.

Thereafter, the access point calculates a load state for each band for the dual band of the WLAN band at each predetermined cycle by the load calculation unit for each band (S110).

Specifically, as shown in FIG. 4, the load calculation unit for each band analyzes the packet for the dual bands supported by the access point (S111).

Through packet analysis, the load calculation unit for each band detects the number of accessors connected to each of the dual bands, detects a data transmission amount, or detects a packet retransmission rate (S112, S113, S114). The detection process may be applied to only one of the above processes, or two or more processes may be applied to detect two or more types of data.

Subsequently, the load for each band is calculated using the data detected by the load calculator for each band (S115). In the calculation, when two or more types of detected data are assigned, priorities among them may be assigned to calculate a load according to the priority (S116).

It is preferable to calculate and update the load for each band calculated for each predetermined period set by the access point.

Thereafter, as shown in FIG. 3, the access point determines whether the load for each band is greater than or equal to a preset threshold in the load calculation unit for each band (S120).

As a result of the determination, when the load for each band is smaller than the preset threshold, the access point responds to the probe request for the dual band through the connection manager. That is, a probe response frame is transmitted (S130).

As a result of the determination, when the load for each band is greater than or equal to a preset threshold, the access point responds only to a probe request of a relatively low load band through the connection manager. That is, a band with a relatively high load does not send a probe response to a probe request of a WLAN terminal, and a band with a low load is used for a probe request of a WLAN terminal. Send a probe response to the probe.

For example, if the load in the 2.4 GHz band in the dual band is relatively higher than the load in the 5 GHz band, the access point does not send a frame for the probe response, and the relatively high load The low 5 GHz band transmits a frame for a probe response (S140 and S150).

On the contrary, when the load of the 2.4 GHz band is relatively lower than the load of the 5 GHz band, that is, when the load of the 5 GHz band is relatively high, the 2.4 GHz band having a relatively low load requires a probe request of the WLAN terminal. ), And the 5GHz band with a relatively high load does not respond (S160).

According to this process, unlike the conventional case in which all access points for dual bands were displayed in the wireless LAN terminal as a result of scanning adjacent access points, only the access points of dual bands or low load bands are displayed according to the load per band. do.

Therefore, even if the WLAN terminal does not know the load status of each of the dual bands provided by the access point, the WLAN terminal can automatically access a relatively low load band under the control of the access point.

The foregoing description is merely illustrative of the present invention, and various modifications may be made by those skilled in the art without departing from the spirit of the present invention. Therefore, the embodiments disclosed in the specification of the present invention are not intended to limit the present invention. The scope of the present invention should be construed according to the following claims, and all the techniques within the scope of equivalents should be construed as being included in the scope of the present invention.

In the conventional WLAN system, when the access point of the WLAN terminal is gradually increased to the access point supporting the dual band, there is a case in which the load is increased due to excessive access of the WLAN terminal in one frequency band, but in the present invention, the access point is dual band. When the calculated load for each cycle is greater than or equal to the threshold value, the relatively low load band responds to the probe request to distribute the access load of the WLAN terminal. Such technology is a useful invention that has industrial applicability because it is not only available for the related technology but also commercially available or commercially available as well as practically evident as it overcomes the limitations of the existing technology. .

100: access point
200: wireless LAN terminal
110: access management
120: load calculation unit for each band
130: cycle setting unit

Claims (7)

A band-specific load calculation unit configured to calculate a load condition for each band for the dual bands of the WLAN band at each preset period and determine whether the calculated band-specific load is greater than or equal to a preset threshold; And
When the calculated load for each band is greater than or equal to a preset threshold, a band with a relatively low load transmits a probe response frame to a probe request frame of a WLAN terminal to be newly connected, A connection manager that transmits a probe response frame with respect to a probe request frame of the WLAN terminal in a high band
And an access point. The method of claim 1,
The load calculation unit for each band
And a load for each band is calculated by combining one or more target conditions among the number of accessors, data transmission amount, and packet retransmission rate of the dual band. 3. The method of claim 2,
And the load calculation unit for each band gives priority to a target condition for calculating load conditions for each band, and compares relative loads according to priorities. The method of claim 1,
The connection management unit
And when the calculated load for each band is smaller than a preset threshold, the dual band transmits all probe response frames in response to a probe request frame of a WLAN terminal to be newly connected. Calculating, by the access point, the load state for each band for each of the predetermined periods for the dual band of the WLAN band;
Determining whether the access point is equal to or greater than a predetermined threshold value for the band-specific load calculated by the access point;
When the load condition for each band is greater than or equal to a preset threshold, a band having a low load with respect to a probe request frame of a WLAN terminal to which the access point newly connects transmits a probe response frame. Non-transmitting a probe response frame with respect to a probe request frame of the WLAN terminal in a band having a high load;
Load balancing method in an access point comprising a. The method of claim 5, wherein
Calculating the load for each band for the dual band,
And calculating one or more target conditions of the dual band accessor, data transmission amount, and packet retransmission rate. The method of claim 5, wherein
And before the calculating the load for each band, setting the predetermined period at the access point.

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